Project import
diff --git a/linker/Android.bp b/linker/Android.bp
new file mode 100644
index 0000000..39f1da9
--- /dev/null
+++ b/linker/Android.bp
@@ -0,0 +1,148 @@
+cc_library_static {
+ name: "liblinker_malloc",
+ clang: true,
+
+ srcs: [
+ "linker_allocator.cpp",
+ "linker_memory.cpp",
+ ],
+
+ // We need to access Bionic private headers in the linker.
+ include_dirs: ["bionic/libc"],
+}
+
+cc_binary {
+ clang: true,
+
+ srcs: [
+ "dlfcn.cpp",
+ "linker.cpp",
+ "linker_block_allocator.cpp",
+ "linker_dlwarning.cpp",
+ "linker_gdb_support.cpp",
+ "linker_globals.cpp",
+ "linker_libc_support.c",
+ "linker_namespaces.cpp",
+ "linker_logger.cpp",
+ "linker_mapped_file_fragment.cpp",
+ "linker_phdr.cpp",
+ "linker_sdk_versions.cpp",
+ "linker_soinfo.cpp",
+ "linker_utils.cpp",
+ "rt.cpp",
+ ],
+
+ arch: {
+ arm: {
+ srcs: ["arch/arm/begin.S"],
+
+ cflags: ["-D__work_around_b_24465209__"],
+ },
+ arm64: {
+ srcs: ["arch/arm64/begin.S"],
+ },
+ x86: {
+ srcs: ["arch/x86/begin.c"],
+
+ cflags: ["-D__work_around_b_24465209__"],
+ },
+ x86_64: {
+ srcs: ["arch/x86_64/begin.S"],
+ },
+ mips: {
+ srcs: [
+ "arch/mips/begin.S",
+ "linker_mips.cpp",
+ ],
+ },
+ mips64: {
+ srcs: [
+ "arch/mips64/begin.S",
+ "linker_mips.cpp",
+ ],
+ },
+ },
+
+ // We need to access Bionic private headers in the linker.
+ include_dirs: ["bionic/libc"],
+
+ // -shared is used to overwrite the -Bstatic and -static
+ // flags triggered by LOCAL_FORCE_STATIC_EXECUTABLE.
+ // This dynamic linker is actually a shared object linked with static libraries.
+ ldflags: [
+ "-shared",
+ "-Wl,-Bsymbolic",
+ "-Wl,--exclude-libs,ALL",
+ ],
+
+ cflags: [
+ "-fno-stack-protector",
+ "-Wstrict-overflow=5",
+ "-fvisibility=hidden",
+ "-Wall",
+ "-Wextra",
+ "-Wunused",
+ "-Werror",
+ ],
+
+ // TODO: split out the asflags.
+ asflags: [
+ "-fno-stack-protector",
+ "-Wstrict-overflow=5",
+ "-fvisibility=hidden",
+ "-Wall",
+ "-Wextra",
+ "-Wunused",
+ "-Werror",
+ ],
+
+ conlyflags: ["-std=gnu99"],
+
+ cppflags: ["-Wold-style-cast"],
+
+ // we don't want crtbegin.o (because we have begin.o), so unset it
+ // just for this module
+ nocrt: true,
+
+ static_libs: [
+ "libc_nomalloc",
+ "libziparchive",
+ "libutils",
+ "libbase",
+ "libz",
+ "liblog",
+ "libdebuggerd_client",
+
+ // Important: The liblinker_malloc should be the last library in the list
+ // to overwrite any other malloc implementations by other static libraries.
+ "liblinker_malloc"
+ ],
+ static_executable: true,
+
+ name: "linker",
+ multilib: {
+ lib32: {
+ symlinks: ["linker_asan"],
+ },
+ lib64: {
+ suffix: "64",
+ symlinks: ["linker_asan64"],
+ },
+ },
+ target: {
+ android64: {
+ cflags: ["-DTARGET_IS_64_BIT"],
+ },
+ },
+ compile_multilib: "both",
+
+ // Leave the symbols in the shared library so that stack unwinders can produce
+ // meaningful name resolution.
+ strip: {
+ keep_symbols: true,
+ },
+
+ // Insert an extra objcopy step to add prefix to symbols. This is needed to prevent gdb
+ // looking up symbols in the linker by mistake.
+ prefix_symbols: "__dl_",
+}
diff --git a/linker/Android.mk b/linker/Android.mk
new file mode 100644
index 0000000..ea7451c
--- /dev/null
+++ b/linker/Android.mk
@@ -0,0 +1,3 @@
+LOCAL_PATH := $(call my-dir)
+
+include $(call first-makefiles-under,$(LOCAL_PATH))
diff --git a/linker/MODULE_LICENSE_APACHE2 b/linker/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/linker/MODULE_LICENSE_APACHE2
diff --git a/linker/NOTICE b/linker/NOTICE
new file mode 100644
index 0000000..3ba0ff9
--- /dev/null
+++ b/linker/NOTICE
@@ -0,0 +1,220 @@
+Copyright (C) 2007 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2008 The Android Open Source Project
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2012 The Android Open Source Project
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2013 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2013 The Android Open Source Project
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2014 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2015 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2015 The Android Open Source Project
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2016 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-------------------------------------------------------------------
+
+Copyright (C) 2016 The Android Open Source Project
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.
+
+-------------------------------------------------------------------
+
diff --git a/linker/arch/arm/begin.S b/linker/arch/arm/begin.S
new file mode 100644
index 0000000..8cb599b
--- /dev/null
+++ b/linker/arch/arm/begin.S
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <private/bionic_asm.h>
+
+ENTRY(_start)
+ mov r0, sp
+ bl __linker_init
+
+ /* linker init returns the _entry address in the main image */
+ mov pc, r0
+END(_start)
diff --git a/linker/arch/arm64/begin.S b/linker/arch/arm64/begin.S
new file mode 100644
index 0000000..a6ea583
--- /dev/null
+++ b/linker/arch/arm64/begin.S
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <private/bionic_asm.h>
+
+ENTRY(_start)
+ mov x0, sp
+ bl __linker_init
+
+ /* linker init returns the _entry address in the main image */
+ br x0
+END(_start)
diff --git a/linker/arch/mips/begin.S b/linker/arch/mips/begin.S
new file mode 100644
index 0000000..cbe1e37
--- /dev/null
+++ b/linker/arch/mips/begin.S
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+ .text
+ .align 4
+ .type __start,@function
+
+ .ent __start
+ .globl __start
+ .globl _start
+__start:
+_start:
+ .set noreorder
+ bal 1f
+ nop
+1: .cpload $31
+ .set reorder
+
+ /* Discover the load address */
+ la $t0, 1f
+ bal 1f
+1: subu $t0, $ra, $t0
+
+#define DT_PLTGOT 3
+#define DT_MIPS_LOCAL_GOTNO 0x7000000a
+
+ /* Search dynamic table for DT_MIPS_LOCAL_GOTNO and DT_PLTGOT values */
+ la $t1, _DYNAMIC
+ addu $t1, $t0
+ li $t3, DT_PLTGOT
+ li $t4, DT_MIPS_LOCAL_GOTNO
+0:
+ lw $t2, 0($t1)
+ beqz $t2, .Lrelocate_local_got
+
+ bne $t2, $t3, 1f /* DT_PLTGOT? */
+ lw $s0, 4($t1)
+ addu $s0, $t0
+ b 2f
+
+1: bne $t2, $t4, 1f /* DT_MIPS_LOCAL_GOTNO? */
+ lw $s1, 4($t1)
+ b 2f
+
+1:
+2: addu $t1, 8
+ b 0b
+
+.Lrelocate_local_got:
+ /*
+ * Relocate the local GOT entries
+ * got[0] is address of lazy resolver function
+ * got[1] may be used for a GNU extension
+ */
+
+ addu $s0, 4
+ subu $s1, 1
+ lw $t1, ($s0)
+ bgez $t1, 9f
+ addu $s0, 4
+ subu $s1, 1
+ b 9f
+
+1: lw $t1, ($s0)
+ addu $t1, $t0
+ sw $t1, ($s0)
+ addu $s0, 4
+9: subu $s1, 1
+ bgez $s1, 1b
+
+ /* call linker_init */
+ move $a0, $sp
+ addiu $sp, -4*4 /* space for arg saves in linker_init */
+ la $t9, __linker_init
+ jalr $t9
+ move $t9, $v0
+ addu $sp, 4*4 /* restore sp */
+ j $t9
+ .end __start
diff --git a/linker/arch/mips64/begin.S b/linker/arch/mips64/begin.S
new file mode 100644
index 0000000..8f6b94a
--- /dev/null
+++ b/linker/arch/mips64/begin.S
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <private/bionic_asm.h>
+
+#if (_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABI32)
+#define ELF_DYNSZ 8
+#define ELF_DYN_TAG 0
+#define ELF_DYN_VAL 4
+#define GOTENT_SZ 4
+#else
+#define ELF_DYNSZ 16
+#define ELF_DYN_TAG 0
+#define ELF_DYN_VAL 8
+#define GOTENT_SZ 8
+#endif
+
+ .text
+ .align 4
+ .type __start,@function
+
+ .ent __start
+ .globl __start
+ .globl _start
+__start:
+_start:
+ .set noreorder
+ bal 1f
+ nop
+1:
+#if (_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABI32)
+ .cpload ra
+#else
+ .cpsetup ra, $0, 1b
+#endif
+ .set reorder
+
+ /* Discover the load address */
+ LA t0, 1b
+ PTR_SUBU t0, ra, t0
+
+#define DT_PLTGOT 3
+#define DT_MIPS_LOCAL_GOTNO 0x7000000a
+
+ /* Search dynamic table for DT_MIPS_LOCAL_GOTNO and DT_PLTGOT values */
+ LA t1, _DYNAMIC
+ PTR_ADDU t1, t0
+ LI t3, DT_PLTGOT
+ LI ta0, DT_MIPS_LOCAL_GOTNO
+0:
+ REG_L t2, ELF_DYN_TAG(t1)
+ beqz t2, .Lrelocate_local_got
+
+ bne t2, t3, 1f /* DT_PLTGOT? */
+ REG_L s0, ELF_DYN_VAL(t1)
+ PTR_ADDU s0, t0
+ b 2f
+
+1:
+ bne t2, ta0, 2f /* DT_MIPS_LOCAL_GOTNO? */
+ REG_L s1, ELF_DYN_VAL(t1)
+
+2: PTR_ADDU t1, ELF_DYNSZ
+ b 0b
+
+.Lrelocate_local_got:
+ /*
+ * Relocate the local GOT entries
+ * got[0] is address of lazy resolver function
+ * got[1] may be used for a GNU extension
+ */
+
+ PTR_ADDU s0, GOTENT_SZ
+ SUBU s1, 1
+ PTR_L t1, (s0)
+ bgez t1, 9f
+ PTR_ADDU s0, GOTENT_SZ
+ SUBU s1, 1
+ b 9f
+
+1: PTR_L t1, (s0)
+ PTR_ADDU t1, t0
+ PTR_S t1, (s0)
+ PTR_ADDU s0, GOTENT_SZ
+9: SUBU s1, 1
+ bgez s1, 1b
+
+ /* call linker_init */
+ move a0, sp
+#if (_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABI32)
+ PTR_SUBU sp, 4*REGSZ /* space for arg saves in linker_init */
+#endif
+ jal __linker_init
+#if (_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABI32)
+ PTR_ADDU sp, 4*REGSZ /* restore sp */
+#endif
+ move t9, v0
+ j t9
+ .end __start
diff --git a/linker/arch/x86/begin.c b/linker/arch/x86/begin.c
new file mode 100644
index 0000000..051a16a
--- /dev/null
+++ b/linker/arch/x86/begin.c
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdint.h>
+#include <sys/cdefs.h>
+
+extern unsigned __linker_init(void* raw_args);
+
+__LIBC_HIDDEN__ void _start() {
+ void (*start)(void);
+
+ void* raw_args = (void*) ((uintptr_t) __builtin_frame_address(0) + sizeof(void*));
+ start = (void(*)(void))__linker_init(raw_args);
+
+ /* linker init returns (%eax) the _entry address in the main image */
+ /* entry point expects sp to point to raw_args */
+
+ __asm__ (
+ "mov %0, %%esp\n\t"
+ "jmp *%1\n\t"
+ : : "r"(raw_args), "r"(start) :
+ );
+
+ /* Unreachable */
+}
+
+/* Since linker has its own version of crtbegin (this file) it should have */
+/* own version of __stack_chk_fail_local for the case when it's built with */
+/* stack protector feature */
+
+#include "arch-x86/bionic/__stack_chk_fail_local.h"
diff --git a/linker/arch/x86_64/begin.S b/linker/arch/x86_64/begin.S
new file mode 100644
index 0000000..7945a31
--- /dev/null
+++ b/linker/arch/x86_64/begin.S
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <private/bionic_asm.h>
+
+ENTRY(_start)
+ mov %rsp, %rdi
+ call __linker_init
+
+ /* linker init returns (%rax) the _entry address in the main image */
+ jmp *%rax
+END(_start)
diff --git a/linker/dlfcn.cpp b/linker/dlfcn.cpp
new file mode 100644
index 0000000..3ac61d7
--- /dev/null
+++ b/linker/dlfcn.cpp
@@ -0,0 +1,288 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker.h"
+#include "linker_globals.h"
+#include "linker_dlwarning.h"
+
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <android/api-level.h>
+
+#include <bionic/pthread_internal.h>
+#include "private/bionic_tls.h"
+#include "private/ScopedPthreadMutexLocker.h"
+#include "private/ThreadLocalBuffer.h"
+
+/* This file hijacks the symbols stubbed out in libdl.so. */
+
+static pthread_mutex_t g_dl_mutex = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
+
+static char* __bionic_set_dlerror(char* new_value) {
+ char** dlerror_slot = &reinterpret_cast<char**>(__get_tls())[TLS_SLOT_DLERROR];
+
+ char* old_value = *dlerror_slot;
+ *dlerror_slot = new_value;
+ return old_value;
+}
+
+static void __bionic_format_dlerror(const char* msg, const char* detail) {
+ char* buffer = __get_thread()->dlerror_buffer;
+ strlcpy(buffer, msg, __BIONIC_DLERROR_BUFFER_SIZE);
+ if (detail != nullptr) {
+ strlcat(buffer, ": ", __BIONIC_DLERROR_BUFFER_SIZE);
+ strlcat(buffer, detail, __BIONIC_DLERROR_BUFFER_SIZE);
+ }
+
+ __bionic_set_dlerror(buffer);
+}
+
+char* dlerror() {
+ char* old_value = __bionic_set_dlerror(nullptr);
+ return old_value;
+}
+
+void android_get_LD_LIBRARY_PATH(char* buffer, size_t buffer_size) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ do_android_get_LD_LIBRARY_PATH(buffer, buffer_size);
+}
+
+void android_update_LD_LIBRARY_PATH(const char* ld_library_path) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ do_android_update_LD_LIBRARY_PATH(ld_library_path);
+}
+
+static void* dlopen_ext(const char* filename, int flags,
+ const android_dlextinfo* extinfo, void* caller_addr) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ g_linker_logger.ResetState();
+ void* result = do_dlopen(filename, flags, extinfo, caller_addr);
+ if (result == nullptr) {
+ __bionic_format_dlerror("dlopen failed", linker_get_error_buffer());
+ return nullptr;
+ }
+ return result;
+}
+
+void* android_dlopen_ext(const char* filename, int flags, const android_dlextinfo* extinfo) {
+ void* caller_addr = __builtin_return_address(0);
+ return dlopen_ext(filename, flags, extinfo, caller_addr);
+}
+
+void* dlopen(const char* filename, int flags) {
+ void* caller_addr = __builtin_return_address(0);
+ return dlopen_ext(filename, flags, nullptr, caller_addr);
+}
+
+void* dlsym_impl(void* handle, const char* symbol, const char* version, void* caller_addr) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ g_linker_logger.ResetState();
+ void* result;
+ if (!do_dlsym(handle, symbol, version, caller_addr, &result)) {
+ __bionic_format_dlerror(linker_get_error_buffer(), nullptr);
+ return nullptr;
+ }
+
+ return result;
+}
+
+void* dlsym(void* handle, const char* symbol) {
+ void* caller_addr = __builtin_return_address(0);
+ return dlsym_impl(handle, symbol, nullptr, caller_addr);
+}
+
+void* dlvsym(void* handle, const char* symbol, const char* version) {
+ void* caller_addr = __builtin_return_address(0);
+ return dlsym_impl(handle, symbol, version, caller_addr);
+}
+
+int dladdr(const void* addr, Dl_info* info) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ return do_dladdr(addr, info);
+}
+
+int dlclose(void* handle) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ int result = do_dlclose(handle);
+ if (result != 0) {
+ __bionic_format_dlerror("dlclose failed", linker_get_error_buffer());
+ }
+ return result;
+}
+
+int dl_iterate_phdr(int (*cb)(dl_phdr_info* info, size_t size, void* data), void* data) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ return do_dl_iterate_phdr(cb, data);
+}
+
+void android_set_application_target_sdk_version(uint32_t target) {
+ // lock to avoid modification in the middle of dlopen.
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ set_application_target_sdk_version(target);
+}
+
+uint32_t android_get_application_target_sdk_version() {
+ return get_application_target_sdk_version();
+}
+
+void android_dlwarning(void* obj, void (*f)(void*, const char*)) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ get_dlwarning(obj, f);
+}
+
+bool android_init_namespaces(const char* public_ns_sonames,
+ const char* anon_ns_library_path) {
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+ bool success = init_namespaces(public_ns_sonames, anon_ns_library_path);
+ if (!success) {
+ __bionic_format_dlerror("android_init_namespaces failed", linker_get_error_buffer());
+ }
+
+ return success;
+}
+
+android_namespace_t* android_create_namespace(const char* name,
+ const char* ld_library_path,
+ const char* default_library_path,
+ uint64_t type,
+ const char* permitted_when_isolated_path,
+ android_namespace_t* parent_namespace) {
+ void* caller_addr = __builtin_return_address(0);
+ ScopedPthreadMutexLocker locker(&g_dl_mutex);
+
+ android_namespace_t* result = create_namespace(caller_addr,
+ name,
+ ld_library_path,
+ default_library_path,
+ type,
+ permitted_when_isolated_path,
+ parent_namespace);
+
+ if (result == nullptr) {
+ __bionic_format_dlerror("android_create_namespace failed", linker_get_error_buffer());
+ }
+
+ return result;
+}
+
+// name_offset: starting index of the name in libdl_info.strtab
+#define ELF32_SYM_INITIALIZER(name_offset, value, shndx) \
+ { name_offset, \
+ reinterpret_cast<Elf32_Addr>(value), \
+ /* st_size */ 0, \
+ ((shndx) == 0) ? 0 : (STB_GLOBAL << 4), \
+ /* st_other */ 0, \
+ shndx, \
+ }
+
+#define ELF64_SYM_INITIALIZER(name_offset, value, shndx) \
+ { name_offset, \
+ ((shndx) == 0) ? 0 : (STB_GLOBAL << 4), \
+ /* st_other */ 0, \
+ shndx, \
+ reinterpret_cast<Elf64_Addr>(value), \
+ /* st_size */ 0, \
+ }
+
+static const char ANDROID_LIBDL_STRTAB[] =
+ // 0000000 00011111 111112 22222222 2333333 3333444444444455555555556666666 6667777777777888888888899999 99999
+ // 0123456 78901234 567890 12345678 9012345 6789012345678901234567890123456 7890123456789012345678901234 56789
+ "dlopen\0dlclose\0dlsym\0dlerror\0dladdr\0android_update_LD_LIBRARY_PATH\0android_get_LD_LIBRARY_PATH\0dl_it"
+ // 00000000001 1111111112222222222 3333333333444444444455555555556666666666777 777777788888888889999999999
+ // 01234567890 1234567890123456789 0123456789012345678901234567890123456789012 345678901234567890123456789
+ "erate_phdr\0android_dlopen_ext\0android_set_application_target_sdk_version\0android_get_application_tar"
+ // 0000000000111111 111122222222223333333333 4444444444555555555566666 6666677 777777778888888888
+ // 0123456789012345 678901234567890123456789 0123456789012345678901234 5678901 234567890123456789
+ "get_sdk_version\0android_init_namespaces\0android_create_namespace\0dlvsym\0android_dlwarning\0"
+#if defined(__arm__)
+ // 290
+ "dl_unwind_find_exidx\0"
+#endif
+ ;
+
+static ElfW(Sym) g_libdl_symtab[] = {
+ // Total length of libdl_info.strtab, including trailing 0.
+ // This is actually the STH_UNDEF entry. Technically, it's
+ // supposed to have st_name == 0, but instead, it points to an index
+ // in the strtab with a \0 to make iterating through the symtab easier.
+ ELFW(SYM_INITIALIZER)(sizeof(ANDROID_LIBDL_STRTAB) - 1, nullptr, 0),
+ ELFW(SYM_INITIALIZER)( 0, &dlopen, 1),
+ ELFW(SYM_INITIALIZER)( 7, &dlclose, 1),
+ ELFW(SYM_INITIALIZER)( 15, &dlsym, 1),
+ ELFW(SYM_INITIALIZER)( 21, &dlerror, 1),
+ ELFW(SYM_INITIALIZER)( 29, &dladdr, 1),
+ ELFW(SYM_INITIALIZER)( 36, &android_update_LD_LIBRARY_PATH, 1),
+ ELFW(SYM_INITIALIZER)( 67, &android_get_LD_LIBRARY_PATH, 1),
+ ELFW(SYM_INITIALIZER)( 95, &dl_iterate_phdr, 1),
+ ELFW(SYM_INITIALIZER)(111, &android_dlopen_ext, 1),
+ ELFW(SYM_INITIALIZER)(130, &android_set_application_target_sdk_version, 1),
+ ELFW(SYM_INITIALIZER)(173, &android_get_application_target_sdk_version, 1),
+ ELFW(SYM_INITIALIZER)(216, &android_init_namespaces, 1),
+ ELFW(SYM_INITIALIZER)(240, &android_create_namespace, 1),
+ ELFW(SYM_INITIALIZER)(265, &dlvsym, 1),
+ ELFW(SYM_INITIALIZER)(272, &android_dlwarning, 1),
+#if defined(__arm__)
+ ELFW(SYM_INITIALIZER)(290, &dl_unwind_find_exidx, 1),
+#endif
+};
+
+// Fake out a hash table with a single bucket.
+//
+// A search of the hash table will look through g_libdl_symtab starting with index 1, then
+// use g_libdl_chains to find the next index to look at. g_libdl_chains should be set up to
+// walk through every element in g_libdl_symtab, and then end with 0 (sentinel value).
+//
+// That is, g_libdl_chains should look like { 0, 2, 3, ... N, 0 } where N is the number
+// of actual symbols, or nelems(g_libdl_symtab)-1 (since the first element of g_libdl_symtab is not
+// a real symbol). (See soinfo_elf_lookup().)
+//
+// Note that adding any new symbols here requires stubbing them out in libdl.
+static unsigned g_libdl_buckets[1] = { 1 };
+#if defined(__arm__)
+static unsigned g_libdl_chains[] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 0 };
+#else
+static unsigned g_libdl_chains[] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0 };
+#endif
+
+static uint8_t __libdl_info_buf[sizeof(soinfo)] __attribute__((aligned(8)));
+static soinfo* __libdl_info = nullptr;
+
+// This is used by the dynamic linker. Every process gets these symbols for free.
+soinfo* get_libdl_info() {
+ if (__libdl_info == nullptr) {
+ __libdl_info = new (__libdl_info_buf) soinfo(&g_default_namespace, "libdl.so", nullptr, 0, RTLD_GLOBAL);
+ __libdl_info->flags_ |= FLAG_LINKED;
+ __libdl_info->strtab_ = ANDROID_LIBDL_STRTAB;
+ __libdl_info->symtab_ = g_libdl_symtab;
+ __libdl_info->nbucket_ = sizeof(g_libdl_buckets)/sizeof(unsigned);
+ __libdl_info->nchain_ = sizeof(g_libdl_chains)/sizeof(unsigned);
+ __libdl_info->bucket_ = g_libdl_buckets;
+ __libdl_info->chain_ = g_libdl_chains;
+ __libdl_info->ref_count_ = 1;
+ __libdl_info->strtab_size_ = sizeof(ANDROID_LIBDL_STRTAB);
+ __libdl_info->local_group_root_ = __libdl_info;
+ __libdl_info->soname_ = "libdl.so";
+ __libdl_info->target_sdk_version_ = __ANDROID_API__;
+ __libdl_info->generate_handle();
+#if defined(__work_around_b_24465209__)
+ strlcpy(__libdl_info->old_name_, __libdl_info->soname_, sizeof(__libdl_info->old_name_));
+#endif
+ }
+
+ return __libdl_info;
+}
diff --git a/linker/linked_list.h b/linker/linked_list.h
new file mode 100644
index 0000000..092e831
--- /dev/null
+++ b/linker/linked_list.h
@@ -0,0 +1,241 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LINKED_LIST_H
+#define __LINKED_LIST_H
+
+#include "private/bionic_macros.h"
+
+template<typename T>
+struct LinkedListEntry {
+ LinkedListEntry<T>* next;
+ T* element;
+};
+
+// ForwardInputIterator
+template<typename T>
+class LinkedListIterator {
+ public:
+ LinkedListIterator() : entry_(nullptr) {}
+ LinkedListIterator(const LinkedListIterator<T>& that) : entry_(that.entry_) {}
+ explicit LinkedListIterator(LinkedListEntry<T>* entry) : entry_(entry) {}
+
+ LinkedListIterator<T>& operator=(const LinkedListIterator<T>& that) {
+ entry_ = that.entry_;
+ return *this;
+ }
+
+ LinkedListIterator<T>& operator++() {
+ entry_ = entry_->next;
+ return *this;
+ }
+
+ T* const operator*() {
+ return entry_->element;
+ }
+
+ bool operator==(const LinkedListIterator<T>& that) const {
+ return entry_ == that.entry_;
+ }
+
+ bool operator!=(const LinkedListIterator<T>& that) const {
+ return entry_ != that.entry_;
+ }
+
+ private:
+ LinkedListEntry<T> *entry_;
+};
+
+/*
+ * Represents linked list of objects of type T
+ */
+template<typename T, typename Allocator>
+class LinkedList {
+ public:
+ typedef LinkedListIterator<T> iterator;
+ typedef T* value_type;
+
+ LinkedList() : head_(nullptr), tail_(nullptr) {}
+ ~LinkedList() {
+ clear();
+ }
+
+ LinkedList(LinkedList&& that) {
+ this->head_ = that.head_;
+ this->tail_ = that.tail_;
+ that.head_ = that.tail_ = nullptr;
+ }
+
+ void push_front(T* const element) {
+ LinkedListEntry<T>* new_entry = Allocator::alloc();
+ new_entry->next = head_;
+ new_entry->element = element;
+ head_ = new_entry;
+ if (tail_ == nullptr) {
+ tail_ = new_entry;
+ }
+ }
+
+ void push_back(T* const element) {
+ LinkedListEntry<T>* new_entry = Allocator::alloc();
+ new_entry->next = nullptr;
+ new_entry->element = element;
+ if (tail_ == nullptr) {
+ tail_ = head_ = new_entry;
+ } else {
+ tail_->next = new_entry;
+ tail_ = new_entry;
+ }
+ }
+
+ T* pop_front() {
+ if (head_ == nullptr) {
+ return nullptr;
+ }
+
+ LinkedListEntry<T>* entry = head_;
+ T* element = entry->element;
+ head_ = entry->next;
+ Allocator::free(entry);
+
+ if (head_ == nullptr) {
+ tail_ = nullptr;
+ }
+
+ return element;
+ }
+
+ T* front() const {
+ if (head_ == nullptr) {
+ return nullptr;
+ }
+
+ return head_->element;
+ }
+
+ void clear() {
+ while (head_ != nullptr) {
+ LinkedListEntry<T>* p = head_;
+ head_ = head_->next;
+ Allocator::free(p);
+ }
+
+ tail_ = nullptr;
+ }
+
+ template<typename F>
+ void for_each(F action) const {
+ visit([&] (T* si) {
+ action(si);
+ return true;
+ });
+ }
+
+ template<typename F>
+ bool visit(F action) const {
+ for (LinkedListEntry<T>* e = head_; e != nullptr; e = e->next) {
+ if (!action(e->element)) {
+ return false;
+ }
+ }
+ return true;
+ }
+
+ template<typename F>
+ void remove_if(F predicate) {
+ for (LinkedListEntry<T>* e = head_, *p = nullptr; e != nullptr;) {
+ if (predicate(e->element)) {
+ LinkedListEntry<T>* next = e->next;
+ if (p == nullptr) {
+ head_ = next;
+ } else {
+ p->next = next;
+ }
+
+ if (tail_ == e) {
+ tail_ = p;
+ }
+
+ Allocator::free(e);
+
+ e = next;
+ } else {
+ p = e;
+ e = e->next;
+ }
+ }
+ }
+
+ template<typename F>
+ T* find_if(F predicate) const {
+ for (LinkedListEntry<T>* e = head_; e != nullptr; e = e->next) {
+ if (predicate(e->element)) {
+ return e->element;
+ }
+ }
+
+ return nullptr;
+ }
+
+ iterator begin() const {
+ return iterator(head_);
+ }
+
+ iterator end() const {
+ return iterator(nullptr);
+ }
+
+ iterator find(T* value) const {
+ for (LinkedListEntry<T>* e = head_; e != nullptr; e = e->next) {
+ if (e->element == value) {
+ return iterator(e);
+ }
+ }
+
+ return end();
+ }
+
+ size_t copy_to_array(T* array[], size_t array_length) const {
+ size_t sz = 0;
+ for (LinkedListEntry<T>* e = head_; sz < array_length && e != nullptr; e = e->next) {
+ array[sz++] = e->element;
+ }
+
+ return sz;
+ }
+
+ bool contains(const T* el) const {
+ for (LinkedListEntry<T>* e = head_; e != nullptr; e = e->next) {
+ if (e->element == el) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ static LinkedList make_list(T* const element) {
+ LinkedList<T, Allocator> one_element_list;
+ one_element_list.push_back(element);
+ return one_element_list;
+ }
+
+ private:
+ LinkedListEntry<T>* head_;
+ LinkedListEntry<T>* tail_;
+ DISALLOW_COPY_AND_ASSIGN(LinkedList);
+};
+
+#endif // __LINKED_LIST_H
diff --git a/linker/linker.cpp b/linker/linker.cpp
new file mode 100644
index 0000000..d2a6e7d
--- /dev/null
+++ b/linker/linker.cpp
@@ -0,0 +1,3678 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <android/api-level.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+#include <new>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+// Private C library headers.
+#include "private/bionic_globals.h"
+#include "private/bionic_tls.h"
+#include "private/KernelArgumentBlock.h"
+#include "private/ScopedPthreadMutexLocker.h"
+#include "private/ScopeGuard.h"
+
+#include "linker.h"
+#include "linker_block_allocator.h"
+#include "linker_gdb_support.h"
+#include "linker_globals.h"
+#include "linker_debug.h"
+#include "linker_dlwarning.h"
+#include "linker_namespaces.h"
+#include "linker_sleb128.h"
+#include "linker_phdr.h"
+#include "linker_relocs.h"
+#include "linker_reloc_iterators.h"
+#include "linker_utils.h"
+
+#include "android-base/strings.h"
+#include "android-base/stringprintf.h"
+#include "debuggerd/client.h"
+#include "ziparchive/zip_archive.h"
+
+extern void __libc_init_globals(KernelArgumentBlock&);
+extern void __libc_init_AT_SECURE(KernelArgumentBlock&);
+
+extern "C" void _start();
+
+// Override macros to use C++ style casts.
+#undef ELF_ST_TYPE
+#define ELF_ST_TYPE(x) (static_cast<uint32_t>(x) & 0xf)
+
+static android_namespace_t* g_anonymous_namespace = &g_default_namespace;
+
+static ElfW(Addr) get_elf_exec_load_bias(const ElfW(Ehdr)* elf);
+
+static LinkerTypeAllocator<soinfo> g_soinfo_allocator;
+static LinkerTypeAllocator<LinkedListEntry<soinfo>> g_soinfo_links_allocator;
+
+static LinkerTypeAllocator<android_namespace_t> g_namespace_allocator;
+static LinkerTypeAllocator<LinkedListEntry<android_namespace_t>> g_namespace_list_allocator;
+
+static soinfo* solist;
+static soinfo* sonext;
+static soinfo* somain; // main process, always the one after libdl_info
+
+#if defined(__LP64__)
+static const char* const kSystemLibDir = "/system/lib64";
+static const char* const kVendorLibDir = "/vendor/lib64";
+static const char* const kAsanSystemLibDir = "/data/lib64";
+static const char* const kAsanVendorLibDir = "/data/vendor/lib64";
+#else
+static const char* const kSystemLibDir = "/system/lib";
+static const char* const kVendorLibDir = "/vendor/lib";
+static const char* const kAsanSystemLibDir = "/data/lib";
+static const char* const kAsanVendorLibDir = "/data/vendor/lib";
+#endif
+
+static const char* const kDefaultLdPaths[] = {
+ kSystemLibDir,
+ kVendorLibDir,
+ nullptr
+};
+
+static const char* const kAsanDefaultLdPaths[] = {
+ kAsanSystemLibDir,
+ kSystemLibDir,
+ kAsanVendorLibDir,
+ kVendorLibDir,
+ nullptr
+};
+
+// Is ASAN enabled?
+static bool g_is_asan = false;
+
+static bool is_system_library(const std::string& realpath) {
+ for (const auto& dir : g_default_namespace.get_default_library_paths()) {
+ if (file_is_in_dir(realpath, dir)) {
+ return true;
+ }
+ }
+ return false;
+}
+
+// Checks if the file exists and not a directory.
+static bool file_exists(const char* path) {
+ struct stat s;
+
+ if (stat(path, &s) != 0) {
+ return false;
+ }
+
+ return S_ISREG(s.st_mode);
+}
+
+// TODO(dimitry): The grey-list is a workaround for http://b/26394120 ---
+// gradually remove libraries from this list until it is gone.
+static bool is_greylisted(const char* name, const soinfo* needed_by) {
+ static const char* const kLibraryGreyList[] = {
+ "libandroid_runtime.so",
+ "libbinder.so",
+ "libcrypto.so",
+ "libcutils.so",
+ "libexpat.so",
+ "libgui.so",
+ "libmedia.so",
+ "libnativehelper.so",
+ "libskia.so",
+ "libssl.so",
+ "libstagefright.so",
+ "libsqlite.so",
+ "libui.so",
+ "libutils.so",
+ "libvorbisidec.so",
+ nullptr
+ };
+
+ // limit greylisting to apps targeting sdk version 23 and below
+ if (get_application_target_sdk_version() > 23) {
+ return false;
+ }
+
+ // if the library needed by a system library - implicitly assume it
+ // is greylisted
+
+ if (needed_by != nullptr && is_system_library(needed_by->get_realpath())) {
+ return true;
+ }
+
+ // if this is an absolute path - make sure it points to /system/lib(64)
+ if (name[0] == '/' && dirname(name) == kSystemLibDir) {
+ // and reduce the path to basename
+ name = basename(name);
+ }
+
+ for (size_t i = 0; kLibraryGreyList[i] != nullptr; ++i) {
+ if (strcmp(name, kLibraryGreyList[i]) == 0) {
+ return true;
+ }
+ }
+
+ return false;
+}
+// END OF WORKAROUND
+
+static const char* const* g_default_ld_paths;
+static std::vector<std::string> g_ld_preload_names;
+
+static std::vector<soinfo*> g_ld_preloads;
+
+static bool g_public_namespace_initialized;
+static soinfo_list_t g_public_namespace;
+
+int g_ld_debug_verbosity;
+abort_msg_t* g_abort_message = nullptr; // For debuggerd.
+
+#if STATS
+struct linker_stats_t {
+ int count[kRelocMax];
+};
+
+static linker_stats_t linker_stats;
+
+void count_relocation(RelocationKind kind) {
+ ++linker_stats.count[kind];
+}
+#else
+void count_relocation(RelocationKind) {
+}
+#endif
+
+#if COUNT_PAGES
+uint32_t bitmask[4096];
+#endif
+
+static void notify_gdb_of_load(soinfo* info) {
+ if (info->is_linker() || info->is_main_executable()) {
+ // gdb already knows about the linker and the main executable.
+ return;
+ }
+
+ link_map* map = &(info->link_map_head);
+
+ map->l_addr = info->load_bias;
+ // link_map l_name field is not const.
+ map->l_name = const_cast<char*>(info->get_realpath());
+ map->l_ld = info->dynamic;
+
+ CHECK(map->l_name != nullptr);
+ CHECK(map->l_name[0] != '\0');
+
+ notify_gdb_of_load(map);
+}
+
+static void notify_gdb_of_unload(soinfo* info) {
+ notify_gdb_of_unload(&(info->link_map_head));
+}
+
+LinkedListEntry<soinfo>* SoinfoListAllocator::alloc() {
+ return g_soinfo_links_allocator.alloc();
+}
+
+void SoinfoListAllocator::free(LinkedListEntry<soinfo>* entry) {
+ g_soinfo_links_allocator.free(entry);
+}
+
+LinkedListEntry<android_namespace_t>* NamespaceListAllocator::alloc() {
+ return g_namespace_list_allocator.alloc();
+}
+
+void NamespaceListAllocator::free(LinkedListEntry<android_namespace_t>* entry) {
+ g_namespace_list_allocator.free(entry);
+}
+
+static soinfo* soinfo_alloc(android_namespace_t* ns, const char* name,
+ struct stat* file_stat, off64_t file_offset,
+ uint32_t rtld_flags) {
+ if (strlen(name) >= PATH_MAX) {
+ DL_ERR("library name \"%s\" too long", name);
+ return nullptr;
+ }
+
+ soinfo* si = new (g_soinfo_allocator.alloc()) soinfo(ns, name, file_stat,
+ file_offset, rtld_flags);
+
+ sonext->next = si;
+ sonext = si;
+
+ si->generate_handle();
+ ns->add_soinfo(si);
+
+ TRACE("name %s: allocated soinfo @ %p", name, si);
+ return si;
+}
+
+static void soinfo_free(soinfo* si) {
+ if (si == nullptr) {
+ return;
+ }
+
+ if (si->base != 0 && si->size != 0) {
+ if (!si->is_mapped_by_caller()) {
+ munmap(reinterpret_cast<void*>(si->base), si->size);
+ } else {
+ // remap the region as PROT_NONE, MAP_ANONYMOUS | MAP_NORESERVE
+ mmap(reinterpret_cast<void*>(si->base), si->size, PROT_NONE,
+ MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
+ }
+ }
+
+ soinfo *prev = nullptr, *trav;
+
+ TRACE("name %s: freeing soinfo @ %p", si->get_realpath(), si);
+
+ for (trav = solist; trav != nullptr; trav = trav->next) {
+ if (trav == si) {
+ break;
+ }
+ prev = trav;
+ }
+
+ if (trav == nullptr) {
+ // si was not in solist
+ DL_ERR("name \"%s\"@%p is not in solist!", si->get_realpath(), si);
+ return;
+ }
+
+ // clear links to/from si
+ si->remove_all_links();
+
+ // prev will never be null, because the first entry in solist is
+ // always the static libdl_info.
+ prev->next = si->next;
+ if (si == sonext) {
+ sonext = prev;
+ }
+
+ si->~soinfo();
+ g_soinfo_allocator.free(si);
+}
+
+static void parse_path(const char* path, const char* delimiters,
+ std::vector<std::string>* resolved_paths) {
+ std::vector<std::string> paths;
+ split_path(path, delimiters, &paths);
+ resolve_paths(paths, resolved_paths);
+}
+
+static void parse_LD_LIBRARY_PATH(const char* path) {
+ std::vector<std::string> ld_libary_paths;
+ parse_path(path, ":", &ld_libary_paths);
+ g_default_namespace.set_ld_library_paths(std::move(ld_libary_paths));
+}
+
+static void parse_LD_PRELOAD(const char* path) {
+ g_ld_preload_names.clear();
+ if (path != nullptr) {
+ // We have historically supported ':' as well as ' ' in LD_PRELOAD.
+ g_ld_preload_names = android::base::Split(path, " :");
+ std::remove_if(g_ld_preload_names.begin(),
+ g_ld_preload_names.end(),
+ [] (const std::string& s) { return s.empty(); });
+ }
+}
+
+static bool realpath_fd(int fd, std::string* realpath) {
+ std::vector<char> buf(PATH_MAX), proc_self_fd(PATH_MAX);
+ __libc_format_buffer(&proc_self_fd[0], proc_self_fd.size(), "/proc/self/fd/%d", fd);
+ if (readlink(&proc_self_fd[0], &buf[0], buf.size()) == -1) {
+ PRINT("readlink(\"%s\") failed: %s [fd=%d]", &proc_self_fd[0], strerror(errno), fd);
+ return false;
+ }
+
+ *realpath = &buf[0];
+ return true;
+}
+
+#if defined(__arm__)
+
+// For a given PC, find the .so that it belongs to.
+// Returns the base address of the .ARM.exidx section
+// for that .so, and the number of 8-byte entries
+// in that section (via *pcount).
+//
+// Intended to be called by libc's __gnu_Unwind_Find_exidx().
+//
+// This function is exposed via dlfcn.cpp and libdl.so.
+_Unwind_Ptr dl_unwind_find_exidx(_Unwind_Ptr pc, int* pcount) {
+ uintptr_t addr = reinterpret_cast<uintptr_t>(pc);
+
+ for (soinfo* si = solist; si != 0; si = si->next) {
+ if ((addr >= si->base) && (addr < (si->base + si->size))) {
+ *pcount = si->ARM_exidx_count;
+ return reinterpret_cast<_Unwind_Ptr>(si->ARM_exidx);
+ }
+ }
+ *pcount = 0;
+ return nullptr;
+}
+
+#endif
+
+// Here, we only have to provide a callback to iterate across all the
+// loaded libraries. gcc_eh does the rest.
+int do_dl_iterate_phdr(int (*cb)(dl_phdr_info* info, size_t size, void* data), void* data) {
+ int rv = 0;
+ for (soinfo* si = solist; si != nullptr; si = si->next) {
+ dl_phdr_info dl_info;
+ dl_info.dlpi_addr = si->link_map_head.l_addr;
+ dl_info.dlpi_name = si->link_map_head.l_name;
+ dl_info.dlpi_phdr = si->phdr;
+ dl_info.dlpi_phnum = si->phnum;
+ rv = cb(&dl_info, sizeof(dl_phdr_info), data);
+ if (rv != 0) {
+ break;
+ }
+ }
+ return rv;
+}
+
+
+bool soinfo_do_lookup(soinfo* si_from, const char* name, const version_info* vi,
+ soinfo** si_found_in, const soinfo_list_t& global_group,
+ const soinfo_list_t& local_group, const ElfW(Sym)** symbol) {
+ SymbolName symbol_name(name);
+ const ElfW(Sym)* s = nullptr;
+
+ /* "This element's presence in a shared object library alters the dynamic linker's
+ * symbol resolution algorithm for references within the library. Instead of starting
+ * a symbol search with the executable file, the dynamic linker starts from the shared
+ * object itself. If the shared object fails to supply the referenced symbol, the
+ * dynamic linker then searches the executable file and other shared objects as usual."
+ *
+ * http://www.sco.com/developers/gabi/2012-12-31/ch5.dynamic.html
+ *
+ * Note that this is unlikely since static linker avoids generating
+ * relocations for -Bsymbolic linked dynamic executables.
+ */
+ if (si_from->has_DT_SYMBOLIC) {
+ DEBUG("%s: looking up %s in local scope (DT_SYMBOLIC)", si_from->get_realpath(), name);
+ if (!si_from->find_symbol_by_name(symbol_name, vi, &s)) {
+ return false;
+ }
+
+ if (s != nullptr) {
+ *si_found_in = si_from;
+ }
+ }
+
+ // 1. Look for it in global_group
+ if (s == nullptr) {
+ bool error = false;
+ global_group.visit([&](soinfo* global_si) {
+ DEBUG("%s: looking up %s in %s (from global group)",
+ si_from->get_realpath(), name, global_si->get_realpath());
+ if (!global_si->find_symbol_by_name(symbol_name, vi, &s)) {
+ error = true;
+ return false;
+ }
+
+ if (s != nullptr) {
+ *si_found_in = global_si;
+ return false;
+ }
+
+ return true;
+ });
+
+ if (error) {
+ return false;
+ }
+ }
+
+ // 2. Look for it in the local group
+ if (s == nullptr) {
+ bool error = false;
+ local_group.visit([&](soinfo* local_si) {
+ if (local_si == si_from && si_from->has_DT_SYMBOLIC) {
+ // we already did this - skip
+ return true;
+ }
+
+ DEBUG("%s: looking up %s in %s (from local group)",
+ si_from->get_realpath(), name, local_si->get_realpath());
+ if (!local_si->find_symbol_by_name(symbol_name, vi, &s)) {
+ error = true;
+ return false;
+ }
+
+ if (s != nullptr) {
+ *si_found_in = local_si;
+ return false;
+ }
+
+ return true;
+ });
+
+ if (error) {
+ return false;
+ }
+ }
+
+ if (s != nullptr) {
+ TRACE_TYPE(LOOKUP, "si %s sym %s s->st_value = %p, "
+ "found in %s, base = %p, load bias = %p",
+ si_from->get_realpath(), name, reinterpret_cast<void*>(s->st_value),
+ (*si_found_in)->get_realpath(), reinterpret_cast<void*>((*si_found_in)->base),
+ reinterpret_cast<void*>((*si_found_in)->load_bias));
+ }
+
+ *symbol = s;
+ return true;
+}
+
+class ProtectedDataGuard {
+ public:
+ ProtectedDataGuard() {
+ if (ref_count_++ == 0) {
+ protect_data(PROT_READ | PROT_WRITE);
+ }
+ }
+
+ ~ProtectedDataGuard() {
+ if (ref_count_ == 0) { // overflow
+ __libc_fatal("Too many nested calls to dlopen()");
+ }
+
+ if (--ref_count_ == 0) {
+ protect_data(PROT_READ);
+ }
+ }
+ private:
+ void protect_data(int protection) {
+ g_soinfo_allocator.protect_all(protection);
+ g_soinfo_links_allocator.protect_all(protection);
+ g_namespace_allocator.protect_all(protection);
+ g_namespace_list_allocator.protect_all(protection);
+ }
+
+ static size_t ref_count_;
+};
+
+size_t ProtectedDataGuard::ref_count_ = 0;
+
+// Each size has it's own allocator.
+template<size_t size>
+class SizeBasedAllocator {
+ public:
+ static void* alloc() {
+ return allocator_.alloc();
+ }
+
+ static void free(void* ptr) {
+ allocator_.free(ptr);
+ }
+
+ private:
+ static LinkerBlockAllocator allocator_;
+};
+
+template<size_t size>
+LinkerBlockAllocator SizeBasedAllocator<size>::allocator_(size);
+
+template<typename T>
+class TypeBasedAllocator {
+ public:
+ static T* alloc() {
+ return reinterpret_cast<T*>(SizeBasedAllocator<sizeof(T)>::alloc());
+ }
+
+ static void free(T* ptr) {
+ SizeBasedAllocator<sizeof(T)>::free(ptr);
+ }
+};
+
+class LoadTask {
+ public:
+ struct deleter_t {
+ void operator()(LoadTask* t) {
+ t->~LoadTask();
+ TypeBasedAllocator<LoadTask>::free(t);
+ }
+ };
+
+ static deleter_t deleter;
+
+ static LoadTask* create(const char* name, soinfo* needed_by,
+ std::unordered_map<const soinfo*, ElfReader>* readers_map) {
+ LoadTask* ptr = TypeBasedAllocator<LoadTask>::alloc();
+ return new (ptr) LoadTask(name, needed_by, readers_map);
+ }
+
+ const char* get_name() const {
+ return name_;
+ }
+
+ soinfo* get_needed_by() const {
+ return needed_by_;
+ }
+
+ soinfo* get_soinfo() const {
+ return si_;
+ }
+
+ void set_soinfo(soinfo* si) {
+ si_ = si;
+ }
+
+ off64_t get_file_offset() const {
+ return file_offset_;
+ }
+
+ void set_file_offset(off64_t offset) {
+ file_offset_ = offset;
+ }
+
+ int get_fd() const {
+ return fd_;
+ }
+
+ void set_fd(int fd, bool assume_ownership) {
+ fd_ = fd;
+ close_fd_ = assume_ownership;
+ }
+
+ const android_dlextinfo* get_extinfo() const {
+ return extinfo_;
+ }
+
+ void set_extinfo(const android_dlextinfo* extinfo) {
+ extinfo_ = extinfo;
+ }
+
+ bool is_dt_needed() const {
+ return is_dt_needed_;
+ }
+
+ void set_dt_needed(bool is_dt_needed) {
+ is_dt_needed_ = is_dt_needed;
+ }
+
+ const ElfReader& get_elf_reader() const {
+ CHECK(si_ != nullptr);
+ return (*elf_readers_map_)[si_];
+ }
+
+ ElfReader& get_elf_reader() {
+ CHECK(si_ != nullptr);
+ return (*elf_readers_map_)[si_];
+ }
+
+ std::unordered_map<const soinfo*, ElfReader>* get_readers_map() {
+ return elf_readers_map_;
+ }
+
+ bool read(const char* realpath, off64_t file_size) {
+ ElfReader& elf_reader = get_elf_reader();
+ return elf_reader.Read(realpath, fd_, file_offset_, file_size);
+ }
+
+ bool load() {
+ ElfReader& elf_reader = get_elf_reader();
+ if (!elf_reader.Load(extinfo_)) {
+ return false;
+ }
+
+ si_->base = elf_reader.load_start();
+ si_->size = elf_reader.load_size();
+ si_->set_mapped_by_caller(elf_reader.is_mapped_by_caller());
+ si_->load_bias = elf_reader.load_bias();
+ si_->phnum = elf_reader.phdr_count();
+ si_->phdr = elf_reader.loaded_phdr();
+
+ return true;
+ }
+
+ private:
+ LoadTask(const char* name, soinfo* needed_by,
+ std::unordered_map<const soinfo*, ElfReader>* readers_map)
+ : name_(name), needed_by_(needed_by), si_(nullptr),
+ fd_(-1), close_fd_(false), file_offset_(0), elf_readers_map_(readers_map),
+ is_dt_needed_(false) {}
+
+ ~LoadTask() {
+ if (fd_ != -1 && close_fd_) {
+ close(fd_);
+ }
+ }
+
+ const char* name_;
+ soinfo* needed_by_;
+ soinfo* si_;
+ const android_dlextinfo* extinfo_;
+ int fd_;
+ bool close_fd_;
+ off64_t file_offset_;
+ std::unordered_map<const soinfo*, ElfReader>* elf_readers_map_;
+ // TODO(dimitry): needed by workaround for http://b/26394120 (the grey-list)
+ bool is_dt_needed_;
+ // END OF WORKAROUND
+
+ DISALLOW_IMPLICIT_CONSTRUCTORS(LoadTask);
+};
+
+LoadTask::deleter_t LoadTask::deleter;
+
+template <typename T>
+using linked_list_t = LinkedList<T, TypeBasedAllocator<LinkedListEntry<T>>>;
+
+typedef linked_list_t<soinfo> SoinfoLinkedList;
+typedef linked_list_t<const char> StringLinkedList;
+typedef std::vector<LoadTask*> LoadTaskList;
+
+
+// This function walks down the tree of soinfo dependencies
+// in breadth-first order and
+// * calls action(soinfo* si) for each node, and
+// * terminates walk if action returns false.
+//
+// walk_dependencies_tree returns false if walk was terminated
+// by the action and true otherwise.
+template<typename F>
+static bool walk_dependencies_tree(soinfo* root_soinfos[], size_t root_soinfos_size, F action) {
+ SoinfoLinkedList visit_list;
+ SoinfoLinkedList visited;
+
+ for (size_t i = 0; i < root_soinfos_size; ++i) {
+ visit_list.push_back(root_soinfos[i]);
+ }
+
+ soinfo* si;
+ while ((si = visit_list.pop_front()) != nullptr) {
+ if (visited.contains(si)) {
+ continue;
+ }
+
+ if (!action(si)) {
+ return false;
+ }
+
+ visited.push_back(si);
+
+ si->get_children().for_each([&](soinfo* child) {
+ visit_list.push_back(child);
+ });
+ }
+
+ return true;
+}
+
+
+static const ElfW(Sym)* dlsym_handle_lookup(soinfo* root, soinfo* skip_until,
+ soinfo** found, SymbolName& symbol_name,
+ const version_info* vi) {
+ const ElfW(Sym)* result = nullptr;
+ bool skip_lookup = skip_until != nullptr;
+
+ walk_dependencies_tree(&root, 1, [&](soinfo* current_soinfo) {
+ if (skip_lookup) {
+ skip_lookup = current_soinfo != skip_until;
+ return true;
+ }
+
+ if (!current_soinfo->find_symbol_by_name(symbol_name, vi, &result)) {
+ result = nullptr;
+ return false;
+ }
+
+ if (result != nullptr) {
+ *found = current_soinfo;
+ return false;
+ }
+
+ return true;
+ });
+
+ return result;
+}
+
+static const ElfW(Sym)* dlsym_linear_lookup(android_namespace_t* ns,
+ const char* name,
+ const version_info* vi,
+ soinfo** found,
+ soinfo* caller,
+ void* handle);
+
+// This is used by dlsym(3). It performs symbol lookup only within the
+// specified soinfo object and its dependencies in breadth first order.
+static const ElfW(Sym)* dlsym_handle_lookup(soinfo* si, soinfo** found,
+ const char* name, const version_info* vi) {
+ // According to man dlopen(3) and posix docs in the case when si is handle
+ // of the main executable we need to search not only in the executable and its
+ // dependencies but also in all libraries loaded with RTLD_GLOBAL.
+ //
+ // Since RTLD_GLOBAL is always set for the main executable and all dt_needed shared
+ // libraries and they are loaded in breath-first (correct) order we can just execute
+ // dlsym(RTLD_DEFAULT, ...); instead of doing two stage lookup.
+ if (si == somain) {
+ return dlsym_linear_lookup(&g_default_namespace, name, vi, found, nullptr, RTLD_DEFAULT);
+ }
+
+ SymbolName symbol_name(name);
+ return dlsym_handle_lookup(si, nullptr, found, symbol_name, vi);
+}
+
+/* This is used by dlsym(3) to performs a global symbol lookup. If the
+ start value is null (for RTLD_DEFAULT), the search starts at the
+ beginning of the global solist. Otherwise the search starts at the
+ specified soinfo (for RTLD_NEXT).
+ */
+static const ElfW(Sym)* dlsym_linear_lookup(android_namespace_t* ns,
+ const char* name,
+ const version_info* vi,
+ soinfo** found,
+ soinfo* caller,
+ void* handle) {
+ SymbolName symbol_name(name);
+
+ auto& soinfo_list = ns->soinfo_list();
+ auto start = soinfo_list.begin();
+
+ if (handle == RTLD_NEXT) {
+ if (caller == nullptr) {
+ return nullptr;
+ } else {
+ auto it = soinfo_list.find(caller);
+ CHECK (it != soinfo_list.end());
+ start = ++it;
+ }
+ }
+
+ const ElfW(Sym)* s = nullptr;
+ for (auto it = start, end = soinfo_list.end(); it != end; ++it) {
+ soinfo* si = *it;
+ // Do not skip RTLD_LOCAL libraries in dlsym(RTLD_DEFAULT, ...)
+ // if the library is opened by application with target api level <= 22
+ // See http://b/21565766
+ if ((si->get_rtld_flags() & RTLD_GLOBAL) == 0 && si->get_target_sdk_version() > 22) {
+ continue;
+ }
+
+ if (!si->find_symbol_by_name(symbol_name, vi, &s)) {
+ return nullptr;
+ }
+
+ if (s != nullptr) {
+ *found = si;
+ break;
+ }
+ }
+
+ // If not found - use dlsym_handle_lookup for caller's
+ // local_group unless it is part of the global group in which
+ // case we already did it.
+ if (s == nullptr && caller != nullptr &&
+ (caller->get_rtld_flags() & RTLD_GLOBAL) == 0) {
+ return dlsym_handle_lookup(caller->get_local_group_root(),
+ (handle == RTLD_NEXT) ? caller : nullptr, found, symbol_name, vi);
+ }
+
+ if (s != nullptr) {
+ TRACE_TYPE(LOOKUP, "%s s->st_value = %p, found->base = %p",
+ name, reinterpret_cast<void*>(s->st_value), reinterpret_cast<void*>((*found)->base));
+ }
+
+ return s;
+}
+
+soinfo* find_containing_library(const void* p) {
+ ElfW(Addr) address = reinterpret_cast<ElfW(Addr)>(p);
+ for (soinfo* si = solist; si != nullptr; si = si->next) {
+ if (address >= si->base && address - si->base < si->size) {
+ return si;
+ }
+ }
+ return nullptr;
+}
+
+class ZipArchiveCache {
+ public:
+ ZipArchiveCache() {}
+ ~ZipArchiveCache();
+
+ bool get_or_open(const char* zip_path, ZipArchiveHandle* handle);
+ private:
+ DISALLOW_COPY_AND_ASSIGN(ZipArchiveCache);
+
+ std::unordered_map<std::string, ZipArchiveHandle> cache_;
+};
+
+bool ZipArchiveCache::get_or_open(const char* zip_path, ZipArchiveHandle* handle) {
+ std::string key(zip_path);
+
+ auto it = cache_.find(key);
+ if (it != cache_.end()) {
+ *handle = it->second;
+ return true;
+ }
+
+ int fd = TEMP_FAILURE_RETRY(open(zip_path, O_RDONLY | O_CLOEXEC));
+ if (fd == -1) {
+ return false;
+ }
+
+ if (OpenArchiveFd(fd, "", handle) != 0) {
+ // invalid zip-file (?)
+ CloseArchive(handle);
+ close(fd);
+ return false;
+ }
+
+ cache_[key] = *handle;
+ return true;
+}
+
+ZipArchiveCache::~ZipArchiveCache() {
+ for (const auto& it : cache_) {
+ CloseArchive(it.second);
+ }
+}
+
+static int open_library_in_zipfile(ZipArchiveCache* zip_archive_cache,
+ const char* const input_path,
+ off64_t* file_offset, std::string* realpath) {
+ std::string normalized_path;
+ if (!normalize_path(input_path, &normalized_path)) {
+ return -1;
+ }
+
+ const char* const path = normalized_path.c_str();
+ TRACE("Trying zip file open from path \"%s\" -> normalized \"%s\"", input_path, path);
+
+ // Treat an '!/' separator inside a path as the separator between the name
+ // of the zip file on disk and the subdirectory to search within it.
+ // For example, if path is "foo.zip!/bar/bas/x.so", then we search for
+ // "bar/bas/x.so" within "foo.zip".
+ const char* const separator = strstr(path, kZipFileSeparator);
+ if (separator == nullptr) {
+ return -1;
+ }
+
+ char buf[512];
+ if (strlcpy(buf, path, sizeof(buf)) >= sizeof(buf)) {
+ PRINT("Warning: ignoring very long library path: %s", path);
+ return -1;
+ }
+
+ buf[separator - path] = '\0';
+
+ const char* zip_path = buf;
+ const char* file_path = &buf[separator - path + 2];
+ int fd = TEMP_FAILURE_RETRY(open(zip_path, O_RDONLY | O_CLOEXEC));
+ if (fd == -1) {
+ return -1;
+ }
+
+ ZipArchiveHandle handle;
+ if (!zip_archive_cache->get_or_open(zip_path, &handle)) {
+ // invalid zip-file (?)
+ close(fd);
+ return -1;
+ }
+
+ ZipEntry entry;
+
+ if (FindEntry(handle, ZipString(file_path), &entry) != 0) {
+ // Entry was not found.
+ close(fd);
+ return -1;
+ }
+
+ // Check if it is properly stored
+ if (entry.method != kCompressStored || (entry.offset % PAGE_SIZE) != 0) {
+ close(fd);
+ return -1;
+ }
+
+ *file_offset = entry.offset;
+
+ if (realpath_fd(fd, realpath)) {
+ *realpath += separator;
+ } else {
+ PRINT("warning: unable to get realpath for the library \"%s\". Will use given path.",
+ normalized_path.c_str());
+ *realpath = normalized_path;
+ }
+
+ return fd;
+}
+
+static bool format_path(char* buf, size_t buf_size, const char* path, const char* name) {
+ int n = __libc_format_buffer(buf, buf_size, "%s/%s", path, name);
+ if (n < 0 || n >= static_cast<int>(buf_size)) {
+ PRINT("Warning: ignoring very long library path: %s/%s", path, name);
+ return false;
+ }
+
+ return true;
+}
+
+static int open_library_on_paths(ZipArchiveCache* zip_archive_cache,
+ const char* name, off64_t* file_offset,
+ const std::vector<std::string>& paths,
+ std::string* realpath) {
+ for (const auto& path : paths) {
+ char buf[512];
+ if (!format_path(buf, sizeof(buf), path.c_str(), name)) {
+ continue;
+ }
+
+ int fd = -1;
+ if (strstr(buf, kZipFileSeparator) != nullptr) {
+ fd = open_library_in_zipfile(zip_archive_cache, buf, file_offset, realpath);
+ }
+
+ if (fd == -1) {
+ fd = TEMP_FAILURE_RETRY(open(buf, O_RDONLY | O_CLOEXEC));
+ if (fd != -1) {
+ *file_offset = 0;
+ if (!realpath_fd(fd, realpath)) {
+ PRINT("warning: unable to get realpath for the library \"%s\". Will use given path.", buf);
+ *realpath = buf;
+ }
+ }
+ }
+
+ if (fd != -1) {
+ return fd;
+ }
+ }
+
+ return -1;
+}
+
+static int open_library(android_namespace_t* ns,
+ ZipArchiveCache* zip_archive_cache,
+ const char* name, soinfo *needed_by,
+ off64_t* file_offset, std::string* realpath) {
+ TRACE("[ opening %s ]", name);
+
+ // If the name contains a slash, we should attempt to open it directly and not search the paths.
+ if (strchr(name, '/') != nullptr) {
+ int fd = -1;
+
+ if (strstr(name, kZipFileSeparator) != nullptr) {
+ fd = open_library_in_zipfile(zip_archive_cache, name, file_offset, realpath);
+ }
+
+ if (fd == -1) {
+ fd = TEMP_FAILURE_RETRY(open(name, O_RDONLY | O_CLOEXEC));
+ if (fd != -1) {
+ *file_offset = 0;
+ if (!realpath_fd(fd, realpath)) {
+ PRINT("warning: unable to get realpath for the library \"%s\". Will use given path.", name);
+ *realpath = name;
+ }
+ }
+ }
+
+ return fd;
+ }
+
+ // Otherwise we try LD_LIBRARY_PATH first, and fall back to the default library path
+ int fd = open_library_on_paths(zip_archive_cache, name, file_offset, ns->get_ld_library_paths(), realpath);
+ if (fd == -1 && needed_by != nullptr) {
+ fd = open_library_on_paths(zip_archive_cache, name, file_offset, needed_by->get_dt_runpath(), realpath);
+ // Check if the library is accessible
+ if (fd != -1 && !ns->is_accessible(*realpath)) {
+ fd = -1;
+ }
+ }
+
+ if (fd == -1) {
+ fd = open_library_on_paths(zip_archive_cache, name, file_offset, ns->get_default_library_paths(), realpath);
+ }
+
+ // TODO(dimitry): workaround for http://b/26394120 (the grey-list)
+ if (fd == -1 && ns != &g_default_namespace && is_greylisted(name, needed_by)) {
+ // try searching for it on default_namespace default_library_path
+ fd = open_library_on_paths(zip_archive_cache, name, file_offset,
+ g_default_namespace.get_default_library_paths(), realpath);
+ }
+ // END OF WORKAROUND
+
+ return fd;
+}
+
+static const char* fix_dt_needed(const char* dt_needed, const char* sopath __unused) {
+#if !defined(__LP64__)
+ // Work around incorrect DT_NEEDED entries for old apps: http://b/21364029
+ if (get_application_target_sdk_version() <= 22) {
+ const char* bname = basename(dt_needed);
+ if (bname != dt_needed) {
+ DL_WARN("library \"%s\" has invalid DT_NEEDED entry \"%s\"", sopath, dt_needed);
+ add_dlwarning(sopath, "invalid DT_NEEDED entry", dt_needed);
+ }
+
+ return bname;
+ }
+#endif
+ return dt_needed;
+}
+
+template<typename F>
+static void for_each_dt_needed(const soinfo* si, F action) {
+ for (const ElfW(Dyn)* d = si->dynamic; d->d_tag != DT_NULL; ++d) {
+ if (d->d_tag == DT_NEEDED) {
+ action(fix_dt_needed(si->get_string(d->d_un.d_val), si->get_realpath()));
+ }
+ }
+}
+
+template<typename F>
+static void for_each_dt_needed(const ElfReader& elf_reader, F action) {
+ for (const ElfW(Dyn)* d = elf_reader.dynamic(); d->d_tag != DT_NULL; ++d) {
+ if (d->d_tag == DT_NEEDED) {
+ action(fix_dt_needed(elf_reader.get_string(d->d_un.d_val), elf_reader.name()));
+ }
+ }
+}
+
+static bool load_library(android_namespace_t* ns,
+ LoadTask* task,
+ LoadTaskList* load_tasks,
+ int rtld_flags,
+ const std::string& realpath) {
+ off64_t file_offset = task->get_file_offset();
+ const char* name = task->get_name();
+ const android_dlextinfo* extinfo = task->get_extinfo();
+
+ if ((file_offset % PAGE_SIZE) != 0) {
+ DL_ERR("file offset for the library \"%s\" is not page-aligned: %" PRId64, name, file_offset);
+ return false;
+ }
+ if (file_offset < 0) {
+ DL_ERR("file offset for the library \"%s\" is negative: %" PRId64, name, file_offset);
+ return false;
+ }
+
+ struct stat file_stat;
+ if (TEMP_FAILURE_RETRY(fstat(task->get_fd(), &file_stat)) != 0) {
+ DL_ERR("unable to stat file for the library \"%s\": %s", name, strerror(errno));
+ return false;
+ }
+ if (file_offset >= file_stat.st_size) {
+ DL_ERR("file offset for the library \"%s\" >= file size: %" PRId64 " >= %" PRId64,
+ name, file_offset, file_stat.st_size);
+ return false;
+ }
+
+ // Check for symlink and other situations where
+ // file can have different names, unless ANDROID_DLEXT_FORCE_LOAD is set
+ if (extinfo == nullptr || (extinfo->flags & ANDROID_DLEXT_FORCE_LOAD) == 0) {
+ auto predicate = [&](soinfo* si) {
+ return si->get_st_dev() != 0 &&
+ si->get_st_ino() != 0 &&
+ si->get_st_dev() == file_stat.st_dev &&
+ si->get_st_ino() == file_stat.st_ino &&
+ si->get_file_offset() == file_offset;
+ };
+
+ soinfo* si = ns->soinfo_list().find_if(predicate);
+
+ // check public namespace
+ if (si == nullptr) {
+ si = g_public_namespace.find_if(predicate);
+ if (si != nullptr) {
+ ns->add_soinfo(si);
+ }
+ }
+
+ if (si != nullptr) {
+ TRACE("library \"%s\" is already loaded under different name/path \"%s\" - "
+ "will return existing soinfo", name, si->get_realpath());
+ task->set_soinfo(si);
+ return true;
+ }
+ }
+
+ if ((rtld_flags & RTLD_NOLOAD) != 0) {
+ DL_ERR("library \"%s\" wasn't loaded and RTLD_NOLOAD prevented it", name);
+ return false;
+ }
+
+ if (!ns->is_accessible(realpath)) {
+ // TODO(dimitry): workaround for http://b/26394120 - the grey-list
+ const soinfo* needed_by = task->is_dt_needed() ? task->get_needed_by() : nullptr;
+ if (is_greylisted(name, needed_by)) {
+ // print warning only if needed by non-system library
+ if (needed_by == nullptr || !is_system_library(needed_by->get_realpath())) {
+ const soinfo* needed_or_dlopened_by = task->get_needed_by();
+ const char* sopath = needed_or_dlopened_by == nullptr ? "(unknown)" :
+ needed_or_dlopened_by->get_realpath();
+ DL_WARN("library \"%s\" (\"%s\") needed or dlopened by \"%s\" is not accessible for the namespace \"%s\""
+ " - the access is temporarily granted as a workaround for http://b/26394120, note that the access"
+ " will be removed in future releases of Android.",
+ name, realpath.c_str(), sopath, ns->get_name());
+ add_dlwarning(sopath, "unauthorized access to", name);
+ }
+ } else {
+ // do not load libraries if they are not accessible for the specified namespace.
+ const char* needed_or_dlopened_by = task->get_needed_by() == nullptr ?
+ "(unknown)" :
+ task->get_needed_by()->get_realpath();
+
+ DL_ERR("library \"%s\" needed or dlopened by \"%s\" is not accessible for the namespace \"%s\"",
+ name, needed_or_dlopened_by, ns->get_name());
+
+ PRINT("library \"%s\" (\"%s\") needed or dlopened by \"%s\" is not accessible for the"
+ " namespace: [name=\"%s\", ld_library_paths=\"%s\", default_library_paths=\"%s\","
+ " permitted_paths=\"%s\"]",
+ name, realpath.c_str(),
+ needed_or_dlopened_by,
+ ns->get_name(),
+ android::base::Join(ns->get_ld_library_paths(), ':').c_str(),
+ android::base::Join(ns->get_default_library_paths(), ':').c_str(),
+ android::base::Join(ns->get_permitted_paths(), ':').c_str());
+ return false;
+ }
+ }
+
+ soinfo* si = soinfo_alloc(ns, realpath.c_str(), &file_stat, file_offset, rtld_flags);
+ if (si == nullptr) {
+ return false;
+ }
+
+ task->set_soinfo(si);
+
+ // Read the ELF header and some of the segments.
+ if (!task->read(realpath.c_str(), file_stat.st_size)) {
+ soinfo_free(si);
+ task->set_soinfo(nullptr);
+ return false;
+ }
+
+ // find and set DT_RUNPATH and dt_soname
+ // Note that these field values are temporary and are
+ // going to be overwritten on soinfo::prelink_image
+ // with values from PT_LOAD segments.
+ const ElfReader& elf_reader = task->get_elf_reader();
+ for (const ElfW(Dyn)* d = elf_reader.dynamic(); d->d_tag != DT_NULL; ++d) {
+ if (d->d_tag == DT_RUNPATH) {
+ si->set_dt_runpath(elf_reader.get_string(d->d_un.d_val));
+ }
+ if (d->d_tag == DT_SONAME) {
+ si->set_soname(elf_reader.get_string(d->d_un.d_val));
+ }
+ }
+
+ for_each_dt_needed(task->get_elf_reader(), [&](const char* name) {
+ load_tasks->push_back(LoadTask::create(name, si, task->get_readers_map()));
+ });
+
+ return true;
+}
+
+static bool load_library(android_namespace_t* ns,
+ LoadTask* task,
+ ZipArchiveCache* zip_archive_cache,
+ LoadTaskList* load_tasks,
+ int rtld_flags) {
+ const char* name = task->get_name();
+ soinfo* needed_by = task->get_needed_by();
+ const android_dlextinfo* extinfo = task->get_extinfo();
+
+ off64_t file_offset;
+ std::string realpath;
+ if (extinfo != nullptr && (extinfo->flags & ANDROID_DLEXT_USE_LIBRARY_FD) != 0) {
+ file_offset = 0;
+ if ((extinfo->flags & ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET) != 0) {
+ file_offset = extinfo->library_fd_offset;
+ }
+
+ if (!realpath_fd(extinfo->library_fd, &realpath)) {
+ PRINT("warning: unable to get realpath for the library \"%s\" by extinfo->library_fd. "
+ "Will use given name.", name);
+ realpath = name;
+ }
+
+ task->set_fd(extinfo->library_fd, false);
+ task->set_file_offset(file_offset);
+ return load_library(ns, task, load_tasks, rtld_flags, realpath);
+ }
+
+ // Open the file.
+ int fd = open_library(ns, zip_archive_cache, name, needed_by, &file_offset, &realpath);
+ if (fd == -1) {
+ DL_ERR("library \"%s\" not found", name);
+ return false;
+ }
+
+ task->set_fd(fd, true);
+ task->set_file_offset(file_offset);
+
+ return load_library(ns, task, load_tasks, rtld_flags, realpath);
+}
+
+// Returns true if library was found and false in 2 cases
+// 1. (for default namespace only) The library was found but loaded under different
+// target_sdk_version (*candidate != nullptr)
+// 2. The library was not found by soname (*candidate is nullptr)
+static bool find_loaded_library_by_soname(android_namespace_t* ns,
+ const char* name, soinfo** candidate) {
+ *candidate = nullptr;
+
+ // Ignore filename with path.
+ if (strchr(name, '/') != nullptr) {
+ return false;
+ }
+
+ uint32_t target_sdk_version = get_application_target_sdk_version();
+
+ return !ns->soinfo_list().visit([&](soinfo* si) {
+ const char* soname = si->get_soname();
+ if (soname != nullptr && (strcmp(name, soname) == 0)) {
+ // If the library was opened under different target sdk version
+ // skip this step and try to reopen it. The exceptions are
+ // "libdl.so" and global group. There is no point in skipping
+ // them because relocation process is going to use them
+ // in any case.
+ bool is_libdl = si == solist;
+ if (is_libdl || (si->get_dt_flags_1() & DF_1_GLOBAL) != 0 ||
+ !si->is_linked() || si->get_target_sdk_version() == target_sdk_version ||
+ ns != &g_default_namespace) {
+ *candidate = si;
+ return false;
+ } else if (*candidate == nullptr) {
+ // for the different sdk version in the default namespace
+ // remember the first library.
+ *candidate = si;
+ }
+ }
+
+ return true;
+ });
+}
+
+static bool find_library_internal(android_namespace_t* ns,
+ LoadTask* task,
+ ZipArchiveCache* zip_archive_cache,
+ LoadTaskList* load_tasks,
+ int rtld_flags) {
+ soinfo* candidate;
+
+ if (find_loaded_library_by_soname(ns, task->get_name(), &candidate)) {
+ task->set_soinfo(candidate);
+ return true;
+ }
+
+ if (ns != &g_default_namespace) {
+ // check public namespace
+ candidate = g_public_namespace.find_if([&](soinfo* si) {
+ return strcmp(task->get_name(), si->get_soname()) == 0;
+ });
+
+ if (candidate != nullptr) {
+ ns->add_soinfo(candidate);
+ task->set_soinfo(candidate);
+ return true;
+ }
+ }
+
+ // Library might still be loaded, the accurate detection
+ // of this fact is done by load_library.
+ TRACE("[ \"%s\" find_loaded_library_by_soname failed (*candidate=%s@%p). Trying harder...]",
+ task->get_name(), candidate == nullptr ? "n/a" : candidate->get_realpath(), candidate);
+
+ if (load_library(ns, task, zip_archive_cache, load_tasks, rtld_flags)) {
+ return true;
+ } else {
+ // In case we were unable to load the library but there
+ // is a candidate loaded under the same soname but different
+ // sdk level - return it anyways.
+ if (candidate != nullptr) {
+ task->set_soinfo(candidate);
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static void soinfo_unload(soinfo* si);
+static void soinfo_unload(soinfo* soinfos[], size_t count);
+
+// TODO: this is slightly unusual way to construct
+// the global group for relocation. Not every RTLD_GLOBAL
+// library is included in this group for backwards-compatibility
+// reasons.
+//
+// This group consists of the main executable, LD_PRELOADs
+// and libraries with the DF_1_GLOBAL flag set.
+static soinfo_list_t make_global_group(android_namespace_t* ns) {
+ soinfo_list_t global_group;
+ ns->soinfo_list().for_each([&](soinfo* si) {
+ if ((si->get_dt_flags_1() & DF_1_GLOBAL) != 0) {
+ global_group.push_back(si);
+ }
+ });
+
+ return global_group;
+}
+
+// This function provides a list of libraries to be shared
+// by the namespace. For the default namespace this is the global
+// group (see make_global_group). For all others this is a group
+// of RTLD_GLOBAL libraries (which includes the global group from
+// the default namespace).
+static soinfo_list_t get_shared_group(android_namespace_t* ns) {
+ if (ns == &g_default_namespace) {
+ return make_global_group(ns);
+ }
+
+ soinfo_list_t shared_group;
+ ns->soinfo_list().for_each([&](soinfo* si) {
+ if ((si->get_rtld_flags() & RTLD_GLOBAL) != 0) {
+ shared_group.push_back(si);
+ }
+ });
+
+ return shared_group;
+}
+
+static void shuffle(std::vector<LoadTask*>* v) {
+ for (size_t i = 0, size = v->size(); i < size; ++i) {
+ size_t n = size - i;
+ size_t r = arc4random_uniform(n);
+ std::swap((*v)[n-1], (*v)[r]);
+ }
+}
+
+// add_as_children - add first-level loaded libraries (i.e. library_names[], but
+// not their transitive dependencies) as children of the start_with library.
+// This is false when find_libraries is called for dlopen(), when newly loaded
+// libraries must form a disjoint tree.
+static bool find_libraries(android_namespace_t* ns,
+ soinfo* start_with,
+ const char* const library_names[],
+ size_t library_names_count, soinfo* soinfos[],
+ std::vector<soinfo*>* ld_preloads,
+ size_t ld_preloads_count, int rtld_flags,
+ const android_dlextinfo* extinfo,
+ bool add_as_children) {
+ // Step 0: prepare.
+ LoadTaskList load_tasks;
+ std::unordered_map<const soinfo*, ElfReader> readers_map;
+
+ for (size_t i = 0; i < library_names_count; ++i) {
+ const char* name = library_names[i];
+ load_tasks.push_back(LoadTask::create(name, start_with, &readers_map));
+ }
+
+ // Construct global_group.
+ soinfo_list_t global_group = make_global_group(ns);
+
+ // If soinfos array is null allocate one on stack.
+ // The array is needed in case of failure; for example
+ // when library_names[] = {libone.so, libtwo.so} and libone.so
+ // is loaded correctly but libtwo.so failed for some reason.
+ // In this case libone.so should be unloaded on return.
+ // See also implementation of failure_guard below.
+
+ if (soinfos == nullptr) {
+ size_t soinfos_size = sizeof(soinfo*)*library_names_count;
+ soinfos = reinterpret_cast<soinfo**>(alloca(soinfos_size));
+ memset(soinfos, 0, soinfos_size);
+ }
+
+ // list of libraries to link - see step 2.
+ size_t soinfos_count = 0;
+
+ auto scope_guard = make_scope_guard([&]() {
+ for (LoadTask* t : load_tasks) {
+ LoadTask::deleter(t);
+ }
+ });
+
+ auto failure_guard = make_scope_guard([&]() {
+ // Housekeeping
+ soinfo_unload(soinfos, soinfos_count);
+ });
+
+ ZipArchiveCache zip_archive_cache;
+
+ // Step 1: expand the list of load_tasks to include
+ // all DT_NEEDED libraries (do not load them just yet)
+ for (size_t i = 0; i<load_tasks.size(); ++i) {
+ LoadTask* task = load_tasks[i];
+ soinfo* needed_by = task->get_needed_by();
+
+ bool is_dt_needed = needed_by != nullptr && (needed_by != start_with || add_as_children);
+ task->set_extinfo(is_dt_needed ? nullptr : extinfo);
+ task->set_dt_needed(is_dt_needed);
+
+ if(!find_library_internal(ns, task, &zip_archive_cache, &load_tasks, rtld_flags)) {
+ return false;
+ }
+
+ soinfo* si = task->get_soinfo();
+
+ if (is_dt_needed) {
+ needed_by->add_child(si);
+ }
+
+ if (si->is_linked()) {
+ si->increment_ref_count();
+ }
+
+ // When ld_preloads is not null, the first
+ // ld_preloads_count libs are in fact ld_preloads.
+ if (ld_preloads != nullptr && soinfos_count < ld_preloads_count) {
+ ld_preloads->push_back(si);
+ }
+
+ if (soinfos_count < library_names_count) {
+ soinfos[soinfos_count++] = si;
+ }
+ }
+
+ // Step 2: Load libraries in random order (see b/24047022)
+ LoadTaskList load_list;
+ for (auto&& task : load_tasks) {
+ soinfo* si = task->get_soinfo();
+ auto pred = [&](const LoadTask* t) {
+ return t->get_soinfo() == si;
+ };
+
+ if (!si->is_linked() &&
+ std::find_if(load_list.begin(), load_list.end(), pred) == load_list.end() ) {
+ load_list.push_back(task);
+ }
+ }
+ shuffle(&load_list);
+
+ for (auto&& task : load_list) {
+ if (!task->load()) {
+ return false;
+ }
+ }
+
+ // Step 3: pre-link all DT_NEEDED libraries in breadth first order.
+ for (auto&& task : load_tasks) {
+ soinfo* si = task->get_soinfo();
+ if (!si->is_linked() && !si->prelink_image()) {
+ return false;
+ }
+ }
+
+ // Step 4: Add LD_PRELOADed libraries to the global group for
+ // future runs. There is no need to explicitly add them to
+ // the global group for this run because they are going to
+ // appear in the local group in the correct order.
+ if (ld_preloads != nullptr) {
+ for (auto&& si : *ld_preloads) {
+ si->set_dt_flags_1(si->get_dt_flags_1() | DF_1_GLOBAL);
+ }
+ }
+
+
+ // Step 5: link libraries.
+ soinfo_list_t local_group;
+ walk_dependencies_tree(
+ (start_with != nullptr && add_as_children) ? &start_with : soinfos,
+ (start_with != nullptr && add_as_children) ? 1 : soinfos_count,
+ [&] (soinfo* si) {
+ local_group.push_back(si);
+ return true;
+ });
+
+ // We need to increment ref_count in case
+ // the root of the local group was not linked.
+ bool was_local_group_root_linked = local_group.front()->is_linked();
+
+ bool linked = local_group.visit([&](soinfo* si) {
+ if (!si->is_linked()) {
+ if (!si->link_image(global_group, local_group, extinfo)) {
+ return false;
+ }
+ }
+
+ return true;
+ });
+
+ if (linked) {
+ local_group.for_each([](soinfo* si) {
+ if (!si->is_linked()) {
+ si->set_linked();
+ }
+ });
+
+ failure_guard.disable();
+ }
+
+ if (!was_local_group_root_linked) {
+ local_group.front()->increment_ref_count();
+ }
+
+ return linked;
+}
+
+static soinfo* find_library(android_namespace_t* ns,
+ const char* name, int rtld_flags,
+ const android_dlextinfo* extinfo,
+ soinfo* needed_by) {
+ soinfo* si;
+
+ if (name == nullptr) {
+ si = somain;
+ } else if (!find_libraries(ns, needed_by, &name, 1, &si, nullptr, 0, rtld_flags,
+ extinfo, /* add_as_children */ false)) {
+ return nullptr;
+ }
+
+ return si;
+}
+
+static void soinfo_unload(soinfo* root) {
+ if (root->is_linked()) {
+ root = root->get_local_group_root();
+ }
+
+ if (!root->can_unload()) {
+ TRACE("not unloading \"%s\" - the binary is flagged with NODELETE", root->get_realpath());
+ return;
+ }
+
+ soinfo_unload(&root, 1);
+}
+
+static void soinfo_unload(soinfo* soinfos[], size_t count) {
+ // Note that the library can be loaded but not linked;
+ // in which case there is no root but we still need
+ // to walk the tree and unload soinfos involved.
+ //
+ // This happens on unsuccessful dlopen, when one of
+ // the DT_NEEDED libraries could not be linked/found.
+ if (count == 0) {
+ return;
+ }
+
+ soinfo_list_t unload_list;
+ for (size_t i = 0; i < count; ++i) {
+ soinfo* si = soinfos[i];
+
+ if (si->can_unload()) {
+ size_t ref_count = si->is_linked() ? si->decrement_ref_count() : 0;
+ if (ref_count == 0) {
+ unload_list.push_back(si);
+ } else {
+ TRACE("not unloading '%s' group, decrementing ref_count to %zd",
+ si->get_realpath(), ref_count);
+ }
+ } else {
+ TRACE("not unloading '%s' - the binary is flagged with NODELETE", si->get_realpath());
+ return;
+ }
+ }
+
+ // This is used to identify soinfos outside of the load-group
+ // note that we cannot have > 1 in the array and have any of them
+ // linked. This is why we can safely use the first one.
+ soinfo* root = soinfos[0];
+
+ soinfo_list_t local_unload_list;
+ soinfo_list_t external_unload_list;
+ soinfo* si = nullptr;
+
+ while ((si = unload_list.pop_front()) != nullptr) {
+ if (local_unload_list.contains(si)) {
+ continue;
+ }
+
+ local_unload_list.push_back(si);
+
+ if (si->has_min_version(0)) {
+ soinfo* child = nullptr;
+ while ((child = si->get_children().pop_front()) != nullptr) {
+ TRACE("%s@%p needs to unload %s@%p", si->get_realpath(), si,
+ child->get_realpath(), child);
+
+ if (local_unload_list.contains(child)) {
+ continue;
+ } else if (child->is_linked() && child->get_local_group_root() != root) {
+ external_unload_list.push_back(child);
+ } else {
+ unload_list.push_front(child);
+ }
+ }
+ } else {
+#if !defined(__work_around_b_24465209__)
+ __libc_fatal("soinfo for \"%s\"@%p has no version", si->get_realpath(), si);
+#else
+ PRINT("warning: soinfo for \"%s\"@%p has no version", si->get_realpath(), si);
+ for_each_dt_needed(si, [&] (const char* library_name) {
+ TRACE("deprecated (old format of soinfo): %s needs to unload %s",
+ si->get_realpath(), library_name);
+
+ soinfo* needed = find_library(si->get_primary_namespace(),
+ library_name, RTLD_NOLOAD, nullptr, nullptr);
+
+ if (needed != nullptr) {
+ // Not found: for example if symlink was deleted between dlopen and dlclose
+ // Since we cannot really handle errors at this point - print and continue.
+ PRINT("warning: couldn't find %s needed by %s on unload.",
+ library_name, si->get_realpath());
+ return;
+ } else if (local_unload_list.contains(needed)) {
+ // already visited
+ return;
+ } else if (needed->is_linked() && needed->get_local_group_root() != root) {
+ // external group
+ external_unload_list.push_back(needed);
+ } else {
+ // local group
+ unload_list.push_front(needed);
+ }
+ });
+#endif
+ }
+ }
+
+ local_unload_list.for_each([](soinfo* si) {
+ si->call_destructors();
+ });
+
+ while ((si = local_unload_list.pop_front()) != nullptr) {
+ notify_gdb_of_unload(si);
+ soinfo_free(si);
+ }
+
+ while ((si = external_unload_list.pop_front()) != nullptr) {
+ soinfo_unload(si);
+ }
+}
+
+static std::string symbol_display_name(const char* sym_name, const char* sym_ver) {
+ if (sym_ver == nullptr) {
+ return sym_name;
+ }
+
+ return std::string(sym_name) + ", version " + sym_ver;
+}
+
+static android_namespace_t* get_caller_namespace(soinfo* caller) {
+ return caller != nullptr ? caller->get_primary_namespace() : g_anonymous_namespace;
+}
+
+void do_android_get_LD_LIBRARY_PATH(char* buffer, size_t buffer_size) {
+ // Use basic string manipulation calls to avoid snprintf.
+ // snprintf indirectly calls pthread_getspecific to get the size of a buffer.
+ // When debug malloc is enabled, this call returns 0. This in turn causes
+ // snprintf to do nothing, which causes libraries to fail to load.
+ // See b/17302493 for further details.
+ // Once the above bug is fixed, this code can be modified to use
+ // snprintf again.
+ size_t required_len = 0;
+ for (size_t i = 0; g_default_ld_paths[i] != nullptr; ++i) {
+ required_len += strlen(g_default_ld_paths[i]) + 1;
+ }
+ if (buffer_size < required_len) {
+ __libc_fatal("android_get_LD_LIBRARY_PATH failed, buffer too small: "
+ "buffer len %zu, required len %zu", buffer_size, required_len);
+ }
+ char* end = buffer;
+ for (size_t i = 0; g_default_ld_paths[i] != nullptr; ++i) {
+ if (i > 0) *end++ = ':';
+ end = stpcpy(end, g_default_ld_paths[i]);
+ }
+}
+
+void do_android_update_LD_LIBRARY_PATH(const char* ld_library_path) {
+ parse_LD_LIBRARY_PATH(ld_library_path);
+}
+
+static std::string android_dlextinfo_to_string(const android_dlextinfo* info) {
+ if (info == nullptr) {
+ return "(null)";
+ }
+
+ return android::base::StringPrintf("[flags=0x%" PRIx64 ","
+ " reserved_addr=%p,"
+ " reserved_size=0x%zx,"
+ " relro_fd=%d,"
+ " library_fd=%d,"
+ " library_fd_offset=0x%" PRIx64 ","
+ " library_namespace=%s@%p]",
+ info->flags,
+ info->reserved_addr,
+ info->reserved_size,
+ info->relro_fd,
+ info->library_fd,
+ info->library_fd_offset,
+ (info->flags & ANDROID_DLEXT_USE_NAMESPACE) != 0 ?
+ (info->library_namespace != nullptr ?
+ info->library_namespace->get_name() : "(null)") : "(n/a)",
+ (info->flags & ANDROID_DLEXT_USE_NAMESPACE) != 0 ?
+ info->library_namespace : nullptr);
+}
+
+void* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo,
+ void* caller_addr) {
+ soinfo* const caller = find_containing_library(caller_addr);
+ android_namespace_t* ns = get_caller_namespace(caller);
+
+ LD_LOG(kLogDlopen,
+ "dlopen(name=\"%s\", flags=0x%x, extinfo=%s, caller=\"%s\", caller_ns=%s@%p) ...",
+ name,
+ flags,
+ android_dlextinfo_to_string(extinfo).c_str(),
+ caller == nullptr ? "(null)" : caller->get_realpath(),
+ ns == nullptr ? "(null)" : ns->get_name(),
+ ns);
+
+ auto failure_guard = make_scope_guard([&]() {
+ LD_LOG(kLogDlopen, "... dlopen failed: %s", linker_get_error_buffer());
+ });
+
+ if ((flags & ~(RTLD_NOW|RTLD_LAZY|RTLD_LOCAL|RTLD_GLOBAL|RTLD_NODELETE|RTLD_NOLOAD)) != 0) {
+ DL_ERR("invalid flags to dlopen: %x", flags);
+ return nullptr;
+ }
+
+ if (extinfo != nullptr) {
+ if ((extinfo->flags & ~(ANDROID_DLEXT_VALID_FLAG_BITS)) != 0) {
+ DL_ERR("invalid extended flags to android_dlopen_ext: 0x%" PRIx64, extinfo->flags);
+ return nullptr;
+ }
+
+ if ((extinfo->flags & ANDROID_DLEXT_USE_LIBRARY_FD) == 0 &&
+ (extinfo->flags & ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET) != 0) {
+ DL_ERR("invalid extended flag combination (ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET without "
+ "ANDROID_DLEXT_USE_LIBRARY_FD): 0x%" PRIx64, extinfo->flags);
+ return nullptr;
+ }
+
+ if ((extinfo->flags & ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS) != 0 &&
+ (extinfo->flags & (ANDROID_DLEXT_RESERVED_ADDRESS | ANDROID_DLEXT_RESERVED_ADDRESS_HINT)) != 0) {
+ DL_ERR("invalid extended flag combination: ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS is not "
+ "compatible with ANDROID_DLEXT_RESERVED_ADDRESS/ANDROID_DLEXT_RESERVED_ADDRESS_HINT");
+ return nullptr;
+ }
+
+ if ((extinfo->flags & ANDROID_DLEXT_USE_NAMESPACE) != 0) {
+ if (extinfo->library_namespace == nullptr) {
+ DL_ERR("ANDROID_DLEXT_USE_NAMESPACE is set but extinfo->library_namespace is null");
+ return nullptr;
+ }
+ ns = extinfo->library_namespace;
+ }
+ }
+
+ std::string asan_name_holder;
+
+ const char* translated_name = name;
+ if (g_is_asan) {
+ if (file_is_in_dir(name, kSystemLibDir)) {
+ asan_name_holder = std::string(kAsanSystemLibDir) + "/" + basename(name);
+ if (file_exists(asan_name_holder.c_str())) {
+ translated_name = asan_name_holder.c_str();
+ PRINT("linker_asan dlopen translating \"%s\" -> \"%s\"", name, translated_name);
+ }
+ } else if (file_is_in_dir(name, kVendorLibDir)) {
+ asan_name_holder = std::string(kAsanVendorLibDir) + "/" + basename(name);
+ if (file_exists(asan_name_holder.c_str())) {
+ translated_name = asan_name_holder.c_str();
+ PRINT("linker_asan dlopen translating \"%s\" -> \"%s\"", name, translated_name);
+ }
+ }
+ }
+
+ ProtectedDataGuard guard;
+ soinfo* si = find_library(ns, translated_name, flags, extinfo, caller);
+ if (si != nullptr) {
+ failure_guard.disable();
+ si->call_constructors();
+ void* handle = si->to_handle();
+ LD_LOG(kLogDlopen,
+ "... dlopen successful: realpath=\"%s\", soname=\"%s\", handle=%p",
+ si->get_realpath(), si->get_soname(), handle);
+ return handle;
+ }
+
+ return nullptr;
+}
+
+int do_dladdr(const void* addr, Dl_info* info) {
+ // Determine if this address can be found in any library currently mapped.
+ soinfo* si = find_containing_library(addr);
+ if (si == nullptr) {
+ return 0;
+ }
+
+ memset(info, 0, sizeof(Dl_info));
+
+ info->dli_fname = si->get_realpath();
+ // Address at which the shared object is loaded.
+ info->dli_fbase = reinterpret_cast<void*>(si->base);
+
+ // Determine if any symbol in the library contains the specified address.
+ ElfW(Sym)* sym = si->find_symbol_by_address(addr);
+ if (sym != nullptr) {
+ info->dli_sname = si->get_string(sym->st_name);
+ info->dli_saddr = reinterpret_cast<void*>(si->resolve_symbol_address(sym));
+ }
+
+ return 1;
+}
+
+static soinfo* soinfo_from_handle(void* handle) {
+ if ((reinterpret_cast<uintptr_t>(handle) & 1) != 0) {
+ auto it = g_soinfo_handles_map.find(reinterpret_cast<uintptr_t>(handle));
+ if (it == g_soinfo_handles_map.end()) {
+ return nullptr;
+ } else {
+ return it->second;
+ }
+ }
+
+ return static_cast<soinfo*>(handle);
+}
+
+bool do_dlsym(void* handle, const char* sym_name, const char* sym_ver,
+ void* caller_addr, void** symbol) {
+#if !defined(__LP64__)
+ if (handle == nullptr) {
+ DL_ERR("dlsym failed: library handle is null");
+ return false;
+ }
+#endif
+
+ if (sym_name == nullptr) {
+ DL_ERR("dlsym failed: symbol name is null");
+ return false;
+ }
+
+ soinfo* found = nullptr;
+ const ElfW(Sym)* sym = nullptr;
+ soinfo* caller = find_containing_library(caller_addr);
+ android_namespace_t* ns = get_caller_namespace(caller);
+
+ version_info vi_instance;
+ version_info* vi = nullptr;
+
+ if (sym_ver != nullptr) {
+ vi_instance.name = sym_ver;
+ vi_instance.elf_hash = calculate_elf_hash(sym_ver);
+ vi = &vi_instance;
+ }
+
+ if (handle == RTLD_DEFAULT || handle == RTLD_NEXT) {
+ sym = dlsym_linear_lookup(ns, sym_name, vi, &found, caller, handle);
+ } else {
+ soinfo* si = soinfo_from_handle(handle);
+ if (si == nullptr) {
+ DL_ERR("dlsym failed: invalid handle: %p", handle);
+ return false;
+ }
+ sym = dlsym_handle_lookup(si, &found, sym_name, vi);
+ }
+
+ if (sym != nullptr) {
+ uint32_t bind = ELF_ST_BIND(sym->st_info);
+
+ if ((bind == STB_GLOBAL || bind == STB_WEAK) && sym->st_shndx != 0) {
+ *symbol = reinterpret_cast<void*>(found->resolve_symbol_address(sym));
+ return true;
+ }
+
+ DL_ERR("symbol \"%s\" found but not global", symbol_display_name(sym_name, sym_ver).c_str());
+ return false;
+ }
+
+ DL_ERR("undefined symbol: %s", symbol_display_name(sym_name, sym_ver).c_str());
+ return false;
+}
+
+int do_dlclose(void* handle) {
+ ProtectedDataGuard guard;
+ soinfo* si = soinfo_from_handle(handle);
+ if (si == nullptr) {
+ DL_ERR("invalid handle: %p", handle);
+ return -1;
+ }
+
+ soinfo_unload(si);
+ return 0;
+}
+
+bool init_namespaces(const char* public_ns_sonames, const char* anon_ns_library_path) {
+ if (g_public_namespace_initialized) {
+ DL_ERR("public namespace has already been initialized.");
+ return false;
+ }
+
+ if (public_ns_sonames == nullptr || public_ns_sonames[0] == '\0') {
+ DL_ERR("error initializing public namespace: the list of public libraries is empty.");
+ return false;
+ }
+
+ std::vector<std::string> sonames = android::base::Split(public_ns_sonames, ":");
+
+ ProtectedDataGuard guard;
+
+ auto failure_guard = make_scope_guard([&]() {
+ g_public_namespace.clear();
+ });
+
+ for (const auto& soname : sonames) {
+ soinfo* candidate = nullptr;
+
+ find_loaded_library_by_soname(&g_default_namespace, soname.c_str(), &candidate);
+
+ if (candidate == nullptr) {
+ DL_ERR("error initializing public namespace: a library with soname \"%s\""
+ " was not found in the default namespace", soname.c_str());
+ return false;
+ }
+
+ candidate->set_nodelete();
+ g_public_namespace.push_back(candidate);
+ }
+
+ g_public_namespace_initialized = true;
+
+ // create anonymous namespace
+ // When the caller is nullptr - create_namespace will take global group
+ // from the anonymous namespace, which is fine because anonymous namespace
+ // is still pointing to the default one.
+ android_namespace_t* anon_ns =
+ create_namespace(nullptr, "(anonymous)", nullptr, anon_ns_library_path,
+ ANDROID_NAMESPACE_TYPE_REGULAR, nullptr, &g_default_namespace);
+
+ if (anon_ns == nullptr) {
+ g_public_namespace_initialized = false;
+ return false;
+ }
+ g_anonymous_namespace = anon_ns;
+ failure_guard.disable();
+ return true;
+}
+
+static void add_soinfos_to_namespace(const soinfo_list_t& soinfos, android_namespace_t* ns) {
+ ns->add_soinfos(soinfos);
+ for (auto si : soinfos) {
+ si->add_secondary_namespace(ns);
+ }
+}
+
+android_namespace_t* create_namespace(const void* caller_addr,
+ const char* name,
+ const char* ld_library_path,
+ const char* default_library_path,
+ uint64_t type,
+ const char* permitted_when_isolated_path,
+ android_namespace_t* parent_namespace) {
+ if (!g_public_namespace_initialized) {
+ DL_ERR("cannot create namespace: public namespace is not initialized.");
+ return nullptr;
+ }
+
+ if (parent_namespace == nullptr) {
+ // if parent_namespace is nullptr -> set it to the caller namespace
+ soinfo* caller_soinfo = find_containing_library(caller_addr);
+
+ parent_namespace = caller_soinfo != nullptr ?
+ caller_soinfo->get_primary_namespace() :
+ g_anonymous_namespace;
+ }
+
+ ProtectedDataGuard guard;
+ std::vector<std::string> ld_library_paths;
+ std::vector<std::string> default_library_paths;
+ std::vector<std::string> permitted_paths;
+
+ parse_path(ld_library_path, ":", &ld_library_paths);
+ parse_path(default_library_path, ":", &default_library_paths);
+ parse_path(permitted_when_isolated_path, ":", &permitted_paths);
+
+ android_namespace_t* ns = new (g_namespace_allocator.alloc()) android_namespace_t();
+ ns->set_name(name);
+ ns->set_isolated((type & ANDROID_NAMESPACE_TYPE_ISOLATED) != 0);
+ ns->set_ld_library_paths(std::move(ld_library_paths));
+ ns->set_default_library_paths(std::move(default_library_paths));
+ ns->set_permitted_paths(std::move(permitted_paths));
+
+ if ((type & ANDROID_NAMESPACE_TYPE_SHARED) != 0) {
+ // If shared - clone the parent namespace
+ add_soinfos_to_namespace(parent_namespace->soinfo_list(), ns);
+ } else {
+ // If not shared - copy only the shared group
+ add_soinfos_to_namespace(get_shared_group(parent_namespace), ns);
+ }
+
+ return ns;
+}
+
+ElfW(Addr) call_ifunc_resolver(ElfW(Addr) resolver_addr) {
+ typedef ElfW(Addr) (*ifunc_resolver_t)(void);
+ ifunc_resolver_t ifunc_resolver = reinterpret_cast<ifunc_resolver_t>(resolver_addr);
+ ElfW(Addr) ifunc_addr = ifunc_resolver();
+ TRACE_TYPE(RELO, "Called ifunc_resolver@%p. The result is %p",
+ ifunc_resolver, reinterpret_cast<void*>(ifunc_addr));
+
+ return ifunc_addr;
+}
+
+const version_info* VersionTracker::get_version_info(ElfW(Versym) source_symver) const {
+ if (source_symver < 2 ||
+ source_symver >= version_infos.size() ||
+ version_infos[source_symver].name == nullptr) {
+ return nullptr;
+ }
+
+ return &version_infos[source_symver];
+}
+
+void VersionTracker::add_version_info(size_t source_index,
+ ElfW(Word) elf_hash,
+ const char* ver_name,
+ const soinfo* target_si) {
+ if (source_index >= version_infos.size()) {
+ version_infos.resize(source_index+1);
+ }
+
+ version_infos[source_index].elf_hash = elf_hash;
+ version_infos[source_index].name = ver_name;
+ version_infos[source_index].target_si = target_si;
+}
+
+bool VersionTracker::init_verneed(const soinfo* si_from) {
+ uintptr_t verneed_ptr = si_from->get_verneed_ptr();
+
+ if (verneed_ptr == 0) {
+ return true;
+ }
+
+ size_t verneed_cnt = si_from->get_verneed_cnt();
+
+ for (size_t i = 0, offset = 0; i<verneed_cnt; ++i) {
+ const ElfW(Verneed)* verneed = reinterpret_cast<ElfW(Verneed)*>(verneed_ptr + offset);
+ size_t vernaux_offset = offset + verneed->vn_aux;
+ offset += verneed->vn_next;
+
+ if (verneed->vn_version != 1) {
+ DL_ERR("unsupported verneed[%zd] vn_version: %d (expected 1)", i, verneed->vn_version);
+ return false;
+ }
+
+ const char* target_soname = si_from->get_string(verneed->vn_file);
+ // find it in dependencies
+ soinfo* target_si = si_from->get_children().find_if([&](const soinfo* si) {
+ return si->get_soname() != nullptr && strcmp(si->get_soname(), target_soname) == 0;
+ });
+
+ if (target_si == nullptr) {
+ DL_ERR("cannot find \"%s\" from verneed[%zd] in DT_NEEDED list for \"%s\"",
+ target_soname, i, si_from->get_realpath());
+ return false;
+ }
+
+ for (size_t j = 0; j<verneed->vn_cnt; ++j) {
+ const ElfW(Vernaux)* vernaux = reinterpret_cast<ElfW(Vernaux)*>(verneed_ptr + vernaux_offset);
+ vernaux_offset += vernaux->vna_next;
+
+ const ElfW(Word) elf_hash = vernaux->vna_hash;
+ const char* ver_name = si_from->get_string(vernaux->vna_name);
+ ElfW(Half) source_index = vernaux->vna_other;
+
+ add_version_info(source_index, elf_hash, ver_name, target_si);
+ }
+ }
+
+ return true;
+}
+
+template <typename F>
+static bool for_each_verdef(const soinfo* si, F functor) {
+ if (!si->has_min_version(2)) {
+ return true;
+ }
+
+ uintptr_t verdef_ptr = si->get_verdef_ptr();
+ if (verdef_ptr == 0) {
+ return true;
+ }
+
+ size_t offset = 0;
+
+ size_t verdef_cnt = si->get_verdef_cnt();
+ for (size_t i = 0; i<verdef_cnt; ++i) {
+ const ElfW(Verdef)* verdef = reinterpret_cast<ElfW(Verdef)*>(verdef_ptr + offset);
+ size_t verdaux_offset = offset + verdef->vd_aux;
+ offset += verdef->vd_next;
+
+ if (verdef->vd_version != 1) {
+ DL_ERR("unsupported verdef[%zd] vd_version: %d (expected 1) library: %s",
+ i, verdef->vd_version, si->get_realpath());
+ return false;
+ }
+
+ if ((verdef->vd_flags & VER_FLG_BASE) != 0) {
+ // "this is the version of the file itself. It must not be used for
+ // matching a symbol. It can be used to match references."
+ //
+ // http://www.akkadia.org/drepper/symbol-versioning
+ continue;
+ }
+
+ if (verdef->vd_cnt == 0) {
+ DL_ERR("invalid verdef[%zd] vd_cnt == 0 (version without a name)", i);
+ return false;
+ }
+
+ const ElfW(Verdaux)* verdaux = reinterpret_cast<ElfW(Verdaux)*>(verdef_ptr + verdaux_offset);
+
+ if (functor(i, verdef, verdaux) == true) {
+ break;
+ }
+ }
+
+ return true;
+}
+
+bool find_verdef_version_index(const soinfo* si, const version_info* vi, ElfW(Versym)* versym) {
+ if (vi == nullptr) {
+ *versym = kVersymNotNeeded;
+ return true;
+ }
+
+ *versym = kVersymGlobal;
+
+ return for_each_verdef(si,
+ [&](size_t, const ElfW(Verdef)* verdef, const ElfW(Verdaux)* verdaux) {
+ if (verdef->vd_hash == vi->elf_hash &&
+ strcmp(vi->name, si->get_string(verdaux->vda_name)) == 0) {
+ *versym = verdef->vd_ndx;
+ return true;
+ }
+
+ return false;
+ }
+ );
+}
+
+bool VersionTracker::init_verdef(const soinfo* si_from) {
+ return for_each_verdef(si_from,
+ [&](size_t, const ElfW(Verdef)* verdef, const ElfW(Verdaux)* verdaux) {
+ add_version_info(verdef->vd_ndx, verdef->vd_hash,
+ si_from->get_string(verdaux->vda_name), si_from);
+ return false;
+ }
+ );
+}
+
+bool VersionTracker::init(const soinfo* si_from) {
+ if (!si_from->has_min_version(2)) {
+ return true;
+ }
+
+ return init_verneed(si_from) && init_verdef(si_from);
+}
+
+// TODO (dimitry): Methods below need to be moved out of soinfo
+// and in more isolated file in order minimize dependencies on
+// unnecessary object in the linker binary. Consider making them
+// independent from soinfo (?).
+bool soinfo::lookup_version_info(const VersionTracker& version_tracker, ElfW(Word) sym,
+ const char* sym_name, const version_info** vi) {
+ const ElfW(Versym)* sym_ver_ptr = get_versym(sym);
+ ElfW(Versym) sym_ver = sym_ver_ptr == nullptr ? 0 : *sym_ver_ptr;
+
+ if (sym_ver != VER_NDX_LOCAL && sym_ver != VER_NDX_GLOBAL) {
+ *vi = version_tracker.get_version_info(sym_ver);
+
+ if (*vi == nullptr) {
+ DL_ERR("cannot find verneed/verdef for version index=%d "
+ "referenced by symbol \"%s\" at \"%s\"", sym_ver, sym_name, get_realpath());
+ return false;
+ }
+ } else {
+ // there is no version info
+ *vi = nullptr;
+ }
+
+ return true;
+}
+
+#if !defined(__mips__)
+#if defined(USE_RELA)
+static ElfW(Addr) get_addend(ElfW(Rela)* rela, ElfW(Addr) reloc_addr __unused) {
+ return rela->r_addend;
+}
+#else
+static ElfW(Addr) get_addend(ElfW(Rel)* rel, ElfW(Addr) reloc_addr) {
+ if (ELFW(R_TYPE)(rel->r_info) == R_GENERIC_RELATIVE ||
+ ELFW(R_TYPE)(rel->r_info) == R_GENERIC_IRELATIVE) {
+ return *reinterpret_cast<ElfW(Addr)*>(reloc_addr);
+ }
+ return 0;
+}
+#endif
+
+template<typename ElfRelIteratorT>
+bool soinfo::relocate(const VersionTracker& version_tracker, ElfRelIteratorT&& rel_iterator,
+ const soinfo_list_t& global_group, const soinfo_list_t& local_group) {
+ for (size_t idx = 0; rel_iterator.has_next(); ++idx) {
+ const auto rel = rel_iterator.next();
+ if (rel == nullptr) {
+ return false;
+ }
+
+ ElfW(Word) type = ELFW(R_TYPE)(rel->r_info);
+ ElfW(Word) sym = ELFW(R_SYM)(rel->r_info);
+
+ ElfW(Addr) reloc = static_cast<ElfW(Addr)>(rel->r_offset + load_bias);
+ ElfW(Addr) sym_addr = 0;
+ const char* sym_name = nullptr;
+ ElfW(Addr) addend = get_addend(rel, reloc);
+
+ DEBUG("Processing \"%s\" relocation at index %zd", get_realpath(), idx);
+ if (type == R_GENERIC_NONE) {
+ continue;
+ }
+
+ const ElfW(Sym)* s = nullptr;
+ soinfo* lsi = nullptr;
+
+ if (sym != 0) {
+ sym_name = get_string(symtab_[sym].st_name);
+ const version_info* vi = nullptr;
+
+ if (!lookup_version_info(version_tracker, sym, sym_name, &vi)) {
+ return false;
+ }
+
+ if (!soinfo_do_lookup(this, sym_name, vi, &lsi, global_group, local_group, &s)) {
+ return false;
+ }
+
+ if (s == nullptr) {
+ // We only allow an undefined symbol if this is a weak reference...
+ s = &symtab_[sym];
+ if (ELF_ST_BIND(s->st_info) != STB_WEAK) {
+ DL_ERR("cannot locate symbol \"%s\" referenced by \"%s\"...", sym_name, get_realpath());
+ return false;
+ }
+
+ /* IHI0044C AAELF 4.5.1.1:
+
+ Libraries are not searched to resolve weak references.
+ It is not an error for a weak reference to remain unsatisfied.
+
+ During linking, the value of an undefined weak reference is:
+ - Zero if the relocation type is absolute
+ - The address of the place if the relocation is pc-relative
+ - The address of nominal base address if the relocation
+ type is base-relative.
+ */
+
+ switch (type) {
+ case R_GENERIC_JUMP_SLOT:
+ case R_GENERIC_GLOB_DAT:
+ case R_GENERIC_RELATIVE:
+ case R_GENERIC_IRELATIVE:
+#if defined(__aarch64__)
+ case R_AARCH64_ABS64:
+ case R_AARCH64_ABS32:
+ case R_AARCH64_ABS16:
+#elif defined(__x86_64__)
+ case R_X86_64_32:
+ case R_X86_64_64:
+#elif defined(__arm__)
+ case R_ARM_ABS32:
+#elif defined(__i386__)
+ case R_386_32:
+#endif
+ /*
+ * The sym_addr was initialized to be zero above, or the relocation
+ * code below does not care about value of sym_addr.
+ * No need to do anything.
+ */
+ break;
+#if defined(__x86_64__)
+ case R_X86_64_PC32:
+ sym_addr = reloc;
+ break;
+#elif defined(__i386__)
+ case R_386_PC32:
+ sym_addr = reloc;
+ break;
+#endif
+ default:
+ DL_ERR("unknown weak reloc type %d @ %p (%zu)", type, rel, idx);
+ return false;
+ }
+ } else { // We got a definition.
+#if !defined(__LP64__)
+ // When relocating dso with text_relocation .text segment is
+ // not executable. We need to restore elf flags before resolving
+ // STT_GNU_IFUNC symbol.
+ bool protect_segments = has_text_relocations &&
+ lsi == this &&
+ ELF_ST_TYPE(s->st_info) == STT_GNU_IFUNC;
+ if (protect_segments) {
+ if (phdr_table_protect_segments(phdr, phnum, load_bias) < 0) {
+ DL_ERR("can't protect segments for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ }
+#endif
+ sym_addr = lsi->resolve_symbol_address(s);
+#if !defined(__LP64__)
+ if (protect_segments) {
+ if (phdr_table_unprotect_segments(phdr, phnum, load_bias) < 0) {
+ DL_ERR("can't unprotect loadable segments for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ }
+#endif
+ }
+ count_relocation(kRelocSymbol);
+ }
+
+ switch (type) {
+ case R_GENERIC_JUMP_SLOT:
+ count_relocation(kRelocAbsolute);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO JMP_SLOT %16p <- %16p %s\n",
+ reinterpret_cast<void*>(reloc),
+ reinterpret_cast<void*>(sym_addr + addend), sym_name);
+
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = (sym_addr + addend);
+ break;
+ case R_GENERIC_GLOB_DAT:
+ count_relocation(kRelocAbsolute);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO GLOB_DAT %16p <- %16p %s\n",
+ reinterpret_cast<void*>(reloc),
+ reinterpret_cast<void*>(sym_addr + addend), sym_name);
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = (sym_addr + addend);
+ break;
+ case R_GENERIC_RELATIVE:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO RELATIVE %16p <- %16p\n",
+ reinterpret_cast<void*>(reloc),
+ reinterpret_cast<void*>(load_bias + addend));
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = (load_bias + addend);
+ break;
+ case R_GENERIC_IRELATIVE:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO IRELATIVE %16p <- %16p\n",
+ reinterpret_cast<void*>(reloc),
+ reinterpret_cast<void*>(load_bias + addend));
+ {
+#if !defined(__LP64__)
+ // When relocating dso with text_relocation .text segment is
+ // not executable. We need to restore elf flags for this
+ // particular call.
+ if (has_text_relocations) {
+ if (phdr_table_protect_segments(phdr, phnum, load_bias) < 0) {
+ DL_ERR("can't protect segments for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ }
+#endif
+ ElfW(Addr) ifunc_addr = call_ifunc_resolver(load_bias + addend);
+#if !defined(__LP64__)
+ // Unprotect it afterwards...
+ if (has_text_relocations) {
+ if (phdr_table_unprotect_segments(phdr, phnum, load_bias) < 0) {
+ DL_ERR("can't unprotect loadable segments for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ }
+#endif
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = ifunc_addr;
+ }
+ break;
+
+#if defined(__aarch64__)
+ case R_AARCH64_ABS64:
+ count_relocation(kRelocAbsolute);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO ABS64 %16llx <- %16llx %s\n",
+ reloc, sym_addr + addend, sym_name);
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = sym_addr + addend;
+ break;
+ case R_AARCH64_ABS32:
+ count_relocation(kRelocAbsolute);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO ABS32 %16llx <- %16llx %s\n",
+ reloc, sym_addr + addend, sym_name);
+ {
+ const ElfW(Addr) min_value = static_cast<ElfW(Addr)>(INT32_MIN);
+ const ElfW(Addr) max_value = static_cast<ElfW(Addr)>(UINT32_MAX);
+ if ((min_value <= (sym_addr + addend)) &&
+ ((sym_addr + addend) <= max_value)) {
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = sym_addr + addend;
+ } else {
+ DL_ERR("0x%016llx out of range 0x%016llx to 0x%016llx",
+ sym_addr + addend, min_value, max_value);
+ return false;
+ }
+ }
+ break;
+ case R_AARCH64_ABS16:
+ count_relocation(kRelocAbsolute);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO ABS16 %16llx <- %16llx %s\n",
+ reloc, sym_addr + addend, sym_name);
+ {
+ const ElfW(Addr) min_value = static_cast<ElfW(Addr)>(INT16_MIN);
+ const ElfW(Addr) max_value = static_cast<ElfW(Addr)>(UINT16_MAX);
+ if ((min_value <= (sym_addr + addend)) &&
+ ((sym_addr + addend) <= max_value)) {
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = (sym_addr + addend);
+ } else {
+ DL_ERR("0x%016llx out of range 0x%016llx to 0x%016llx",
+ sym_addr + addend, min_value, max_value);
+ return false;
+ }
+ }
+ break;
+ case R_AARCH64_PREL64:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO REL64 %16llx <- %16llx - %16llx %s\n",
+ reloc, sym_addr + addend, rel->r_offset, sym_name);
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = sym_addr + addend - rel->r_offset;
+ break;
+ case R_AARCH64_PREL32:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO REL32 %16llx <- %16llx - %16llx %s\n",
+ reloc, sym_addr + addend, rel->r_offset, sym_name);
+ {
+ const ElfW(Addr) min_value = static_cast<ElfW(Addr)>(INT32_MIN);
+ const ElfW(Addr) max_value = static_cast<ElfW(Addr)>(UINT32_MAX);
+ if ((min_value <= (sym_addr + addend - rel->r_offset)) &&
+ ((sym_addr + addend - rel->r_offset) <= max_value)) {
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = sym_addr + addend - rel->r_offset;
+ } else {
+ DL_ERR("0x%016llx out of range 0x%016llx to 0x%016llx",
+ sym_addr + addend - rel->r_offset, min_value, max_value);
+ return false;
+ }
+ }
+ break;
+ case R_AARCH64_PREL16:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO REL16 %16llx <- %16llx - %16llx %s\n",
+ reloc, sym_addr + addend, rel->r_offset, sym_name);
+ {
+ const ElfW(Addr) min_value = static_cast<ElfW(Addr)>(INT16_MIN);
+ const ElfW(Addr) max_value = static_cast<ElfW(Addr)>(UINT16_MAX);
+ if ((min_value <= (sym_addr + addend - rel->r_offset)) &&
+ ((sym_addr + addend - rel->r_offset) <= max_value)) {
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = sym_addr + addend - rel->r_offset;
+ } else {
+ DL_ERR("0x%016llx out of range 0x%016llx to 0x%016llx",
+ sym_addr + addend - rel->r_offset, min_value, max_value);
+ return false;
+ }
+ }
+ break;
+
+ case R_AARCH64_COPY:
+ /*
+ * ET_EXEC is not supported so this should not happen.
+ *
+ * http://infocenter.arm.com/help/topic/com.arm.doc.ihi0056b/IHI0056B_aaelf64.pdf
+ *
+ * Section 4.6.11 "Dynamic relocations"
+ * R_AARCH64_COPY may only appear in executable objects where e_type is
+ * set to ET_EXEC.
+ */
+ DL_ERR("%s R_AARCH64_COPY relocations are not supported", get_realpath());
+ return false;
+ case R_AARCH64_TLS_TPREL64:
+ TRACE_TYPE(RELO, "RELO TLS_TPREL64 *** %16llx <- %16llx - %16llx\n",
+ reloc, (sym_addr + addend), rel->r_offset);
+ break;
+ case R_AARCH64_TLS_DTPREL32:
+ TRACE_TYPE(RELO, "RELO TLS_DTPREL32 *** %16llx <- %16llx - %16llx\n",
+ reloc, (sym_addr + addend), rel->r_offset);
+ break;
+#elif defined(__x86_64__)
+ case R_X86_64_32:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO R_X86_64_32 %08zx <- +%08zx %s", static_cast<size_t>(reloc),
+ static_cast<size_t>(sym_addr), sym_name);
+ *reinterpret_cast<Elf32_Addr*>(reloc) = sym_addr + addend;
+ break;
+ case R_X86_64_64:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO R_X86_64_64 %08zx <- +%08zx %s", static_cast<size_t>(reloc),
+ static_cast<size_t>(sym_addr), sym_name);
+ *reinterpret_cast<Elf64_Addr*>(reloc) = sym_addr + addend;
+ break;
+ case R_X86_64_PC32:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO R_X86_64_PC32 %08zx <- +%08zx (%08zx - %08zx) %s",
+ static_cast<size_t>(reloc), static_cast<size_t>(sym_addr - reloc),
+ static_cast<size_t>(sym_addr), static_cast<size_t>(reloc), sym_name);
+ *reinterpret_cast<Elf32_Addr*>(reloc) = sym_addr + addend - reloc;
+ break;
+#elif defined(__arm__)
+ case R_ARM_ABS32:
+ count_relocation(kRelocAbsolute);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO ABS %08x <- %08x %s", reloc, sym_addr, sym_name);
+ *reinterpret_cast<ElfW(Addr)*>(reloc) += sym_addr;
+ break;
+ case R_ARM_REL32:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO REL32 %08x <- %08x - %08x %s",
+ reloc, sym_addr, rel->r_offset, sym_name);
+ *reinterpret_cast<ElfW(Addr)*>(reloc) += sym_addr - rel->r_offset;
+ break;
+ case R_ARM_COPY:
+ /*
+ * ET_EXEC is not supported so this should not happen.
+ *
+ * http://infocenter.arm.com/help/topic/com.arm.doc.ihi0044d/IHI0044D_aaelf.pdf
+ *
+ * Section 4.6.1.10 "Dynamic relocations"
+ * R_ARM_COPY may only appear in executable objects where e_type is
+ * set to ET_EXEC.
+ */
+ DL_ERR("%s R_ARM_COPY relocations are not supported", get_realpath());
+ return false;
+#elif defined(__i386__)
+ case R_386_32:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO R_386_32 %08x <- +%08x %s", reloc, sym_addr, sym_name);
+ *reinterpret_cast<ElfW(Addr)*>(reloc) += sym_addr;
+ break;
+ case R_386_PC32:
+ count_relocation(kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO R_386_PC32 %08x <- +%08x (%08x - %08x) %s",
+ reloc, (sym_addr - reloc), sym_addr, reloc, sym_name);
+ *reinterpret_cast<ElfW(Addr)*>(reloc) += (sym_addr - reloc);
+ break;
+#endif
+ default:
+ DL_ERR("unknown reloc type %d @ %p (%zu)", type, rel, idx);
+ return false;
+ }
+ }
+ return true;
+}
+#endif // !defined(__mips__)
+
+// An empty list of soinfos
+static soinfo_list_t g_empty_list;
+
+bool soinfo::prelink_image() {
+ /* Extract dynamic section */
+ ElfW(Word) dynamic_flags = 0;
+ phdr_table_get_dynamic_section(phdr, phnum, load_bias, &dynamic, &dynamic_flags);
+
+ /* We can't log anything until the linker is relocated */
+ bool relocating_linker = (flags_ & FLAG_LINKER) != 0;
+ if (!relocating_linker) {
+ INFO("[ Linking \"%s\" ]", get_realpath());
+ DEBUG("si->base = %p si->flags = 0x%08x", reinterpret_cast<void*>(base), flags_);
+ }
+
+ if (dynamic == nullptr) {
+ if (!relocating_linker) {
+ DL_ERR("missing PT_DYNAMIC in \"%s\"", get_realpath());
+ }
+ return false;
+ } else {
+ if (!relocating_linker) {
+ DEBUG("dynamic = %p", dynamic);
+ }
+ }
+
+#if defined(__arm__)
+ (void) phdr_table_get_arm_exidx(phdr, phnum, load_bias,
+ &ARM_exidx, &ARM_exidx_count);
+#endif
+
+ // Extract useful information from dynamic section.
+ // Note that: "Except for the DT_NULL element at the end of the array,
+ // and the relative order of DT_NEEDED elements, entries may appear in any order."
+ //
+ // source: http://www.sco.com/developers/gabi/1998-04-29/ch5.dynamic.html
+ uint32_t needed_count = 0;
+ for (ElfW(Dyn)* d = dynamic; d->d_tag != DT_NULL; ++d) {
+ DEBUG("d = %p, d[0](tag) = %p d[1](val) = %p",
+ d, reinterpret_cast<void*>(d->d_tag), reinterpret_cast<void*>(d->d_un.d_val));
+ switch (d->d_tag) {
+ case DT_SONAME:
+ // this is parsed after we have strtab initialized (see below).
+ break;
+
+ case DT_HASH:
+ nbucket_ = reinterpret_cast<uint32_t*>(load_bias + d->d_un.d_ptr)[0];
+ nchain_ = reinterpret_cast<uint32_t*>(load_bias + d->d_un.d_ptr)[1];
+ bucket_ = reinterpret_cast<uint32_t*>(load_bias + d->d_un.d_ptr + 8);
+ chain_ = reinterpret_cast<uint32_t*>(load_bias + d->d_un.d_ptr + 8 + nbucket_ * 4);
+ break;
+
+ case DT_GNU_HASH:
+ gnu_nbucket_ = reinterpret_cast<uint32_t*>(load_bias + d->d_un.d_ptr)[0];
+ // skip symndx
+ gnu_maskwords_ = reinterpret_cast<uint32_t*>(load_bias + d->d_un.d_ptr)[2];
+ gnu_shift2_ = reinterpret_cast<uint32_t*>(load_bias + d->d_un.d_ptr)[3];
+
+ gnu_bloom_filter_ = reinterpret_cast<ElfW(Addr)*>(load_bias + d->d_un.d_ptr + 16);
+ gnu_bucket_ = reinterpret_cast<uint32_t*>(gnu_bloom_filter_ + gnu_maskwords_);
+ // amend chain for symndx = header[1]
+ gnu_chain_ = gnu_bucket_ + gnu_nbucket_ -
+ reinterpret_cast<uint32_t*>(load_bias + d->d_un.d_ptr)[1];
+
+ if (!powerof2(gnu_maskwords_)) {
+ DL_ERR("invalid maskwords for gnu_hash = 0x%x, in \"%s\" expecting power to two",
+ gnu_maskwords_, get_realpath());
+ return false;
+ }
+ --gnu_maskwords_;
+
+ flags_ |= FLAG_GNU_HASH;
+ break;
+
+ case DT_STRTAB:
+ strtab_ = reinterpret_cast<const char*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_STRSZ:
+ strtab_size_ = d->d_un.d_val;
+ break;
+
+ case DT_SYMTAB:
+ symtab_ = reinterpret_cast<ElfW(Sym)*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_SYMENT:
+ if (d->d_un.d_val != sizeof(ElfW(Sym))) {
+ DL_ERR("invalid DT_SYMENT: %zd in \"%s\"",
+ static_cast<size_t>(d->d_un.d_val), get_realpath());
+ return false;
+ }
+ break;
+
+ case DT_PLTREL:
+#if defined(USE_RELA)
+ if (d->d_un.d_val != DT_RELA) {
+ DL_ERR("unsupported DT_PLTREL in \"%s\"; expected DT_RELA", get_realpath());
+ return false;
+ }
+#else
+ if (d->d_un.d_val != DT_REL) {
+ DL_ERR("unsupported DT_PLTREL in \"%s\"; expected DT_REL", get_realpath());
+ return false;
+ }
+#endif
+ break;
+
+ case DT_JMPREL:
+#if defined(USE_RELA)
+ plt_rela_ = reinterpret_cast<ElfW(Rela)*>(load_bias + d->d_un.d_ptr);
+#else
+ plt_rel_ = reinterpret_cast<ElfW(Rel)*>(load_bias + d->d_un.d_ptr);
+#endif
+ break;
+
+ case DT_PLTRELSZ:
+#if defined(USE_RELA)
+ plt_rela_count_ = d->d_un.d_val / sizeof(ElfW(Rela));
+#else
+ plt_rel_count_ = d->d_un.d_val / sizeof(ElfW(Rel));
+#endif
+ break;
+
+ case DT_PLTGOT:
+#if defined(__mips__)
+ // Used by mips and mips64.
+ plt_got_ = reinterpret_cast<ElfW(Addr)**>(load_bias + d->d_un.d_ptr);
+#endif
+ // Ignore for other platforms... (because RTLD_LAZY is not supported)
+ break;
+
+ case DT_DEBUG:
+ // Set the DT_DEBUG entry to the address of _r_debug for GDB
+ // if the dynamic table is writable
+// FIXME: not working currently for N64
+// The flags for the LOAD and DYNAMIC program headers do not agree.
+// The LOAD section containing the dynamic table has been mapped as
+// read-only, but the DYNAMIC header claims it is writable.
+#if !(defined(__mips__) && defined(__LP64__))
+ if ((dynamic_flags & PF_W) != 0) {
+ d->d_un.d_val = reinterpret_cast<uintptr_t>(&_r_debug);
+ }
+#endif
+ break;
+#if defined(USE_RELA)
+ case DT_RELA:
+ rela_ = reinterpret_cast<ElfW(Rela)*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_RELASZ:
+ rela_count_ = d->d_un.d_val / sizeof(ElfW(Rela));
+ break;
+
+ case DT_ANDROID_RELA:
+ android_relocs_ = reinterpret_cast<uint8_t*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_ANDROID_RELASZ:
+ android_relocs_size_ = d->d_un.d_val;
+ break;
+
+ case DT_ANDROID_REL:
+ DL_ERR("unsupported DT_ANDROID_REL in \"%s\"", get_realpath());
+ return false;
+
+ case DT_ANDROID_RELSZ:
+ DL_ERR("unsupported DT_ANDROID_RELSZ in \"%s\"", get_realpath());
+ return false;
+
+ case DT_RELAENT:
+ if (d->d_un.d_val != sizeof(ElfW(Rela))) {
+ DL_ERR("invalid DT_RELAENT: %zd", static_cast<size_t>(d->d_un.d_val));
+ return false;
+ }
+ break;
+
+ // ignored (see DT_RELCOUNT comments for details)
+ case DT_RELACOUNT:
+ break;
+
+ case DT_REL:
+ DL_ERR("unsupported DT_REL in \"%s\"", get_realpath());
+ return false;
+
+ case DT_RELSZ:
+ DL_ERR("unsupported DT_RELSZ in \"%s\"", get_realpath());
+ return false;
+
+#else
+ case DT_REL:
+ rel_ = reinterpret_cast<ElfW(Rel)*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_RELSZ:
+ rel_count_ = d->d_un.d_val / sizeof(ElfW(Rel));
+ break;
+
+ case DT_RELENT:
+ if (d->d_un.d_val != sizeof(ElfW(Rel))) {
+ DL_ERR("invalid DT_RELENT: %zd", static_cast<size_t>(d->d_un.d_val));
+ return false;
+ }
+ break;
+
+ case DT_ANDROID_REL:
+ android_relocs_ = reinterpret_cast<uint8_t*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_ANDROID_RELSZ:
+ android_relocs_size_ = d->d_un.d_val;
+ break;
+
+ case DT_ANDROID_RELA:
+ DL_ERR("unsupported DT_ANDROID_RELA in \"%s\"", get_realpath());
+ return false;
+
+ case DT_ANDROID_RELASZ:
+ DL_ERR("unsupported DT_ANDROID_RELASZ in \"%s\"", get_realpath());
+ return false;
+
+ // "Indicates that all RELATIVE relocations have been concatenated together,
+ // and specifies the RELATIVE relocation count."
+ //
+ // TODO: Spec also mentions that this can be used to optimize relocation process;
+ // Not currently used by bionic linker - ignored.
+ case DT_RELCOUNT:
+ break;
+
+ case DT_RELA:
+ DL_ERR("unsupported DT_RELA in \"%s\"", get_realpath());
+ return false;
+
+ case DT_RELASZ:
+ DL_ERR("unsupported DT_RELASZ in \"%s\"", get_realpath());
+ return false;
+
+#endif
+ case DT_INIT:
+ init_func_ = reinterpret_cast<linker_ctor_function_t>(load_bias + d->d_un.d_ptr);
+ DEBUG("%s constructors (DT_INIT) found at %p", get_realpath(), init_func_);
+ break;
+
+ case DT_FINI:
+ fini_func_ = reinterpret_cast<linker_dtor_function_t>(load_bias + d->d_un.d_ptr);
+ DEBUG("%s destructors (DT_FINI) found at %p", get_realpath(), fini_func_);
+ break;
+
+ case DT_INIT_ARRAY:
+ init_array_ = reinterpret_cast<linker_ctor_function_t*>(load_bias + d->d_un.d_ptr);
+ DEBUG("%s constructors (DT_INIT_ARRAY) found at %p", get_realpath(), init_array_);
+ break;
+
+ case DT_INIT_ARRAYSZ:
+ init_array_count_ = static_cast<uint32_t>(d->d_un.d_val) / sizeof(ElfW(Addr));
+ break;
+
+ case DT_FINI_ARRAY:
+ fini_array_ = reinterpret_cast<linker_dtor_function_t*>(load_bias + d->d_un.d_ptr);
+ DEBUG("%s destructors (DT_FINI_ARRAY) found at %p", get_realpath(), fini_array_);
+ break;
+
+ case DT_FINI_ARRAYSZ:
+ fini_array_count_ = static_cast<uint32_t>(d->d_un.d_val) / sizeof(ElfW(Addr));
+ break;
+
+ case DT_PREINIT_ARRAY:
+ preinit_array_ = reinterpret_cast<linker_ctor_function_t*>(load_bias + d->d_un.d_ptr);
+ DEBUG("%s constructors (DT_PREINIT_ARRAY) found at %p", get_realpath(), preinit_array_);
+ break;
+
+ case DT_PREINIT_ARRAYSZ:
+ preinit_array_count_ = static_cast<uint32_t>(d->d_un.d_val) / sizeof(ElfW(Addr));
+ break;
+
+ case DT_TEXTREL:
+#if defined(__LP64__)
+ DL_ERR("text relocations (DT_TEXTREL) found in 64-bit ELF file \"%s\"", get_realpath());
+ return false;
+#else
+ has_text_relocations = true;
+ break;
+#endif
+
+ case DT_SYMBOLIC:
+ has_DT_SYMBOLIC = true;
+ break;
+
+ case DT_NEEDED:
+ ++needed_count;
+ break;
+
+ case DT_FLAGS:
+ if (d->d_un.d_val & DF_TEXTREL) {
+#if defined(__LP64__)
+ DL_ERR("text relocations (DF_TEXTREL) found in 64-bit ELF file \"%s\"", get_realpath());
+ return false;
+#else
+ has_text_relocations = true;
+#endif
+ }
+ if (d->d_un.d_val & DF_SYMBOLIC) {
+ has_DT_SYMBOLIC = true;
+ }
+ break;
+
+ case DT_FLAGS_1:
+ set_dt_flags_1(d->d_un.d_val);
+
+ if ((d->d_un.d_val & ~SUPPORTED_DT_FLAGS_1) != 0) {
+ DL_WARN("%s: unsupported flags DT_FLAGS_1=%p", get_realpath(), reinterpret_cast<void*>(d->d_un.d_val));
+ }
+ break;
+#if defined(__mips__)
+ case DT_MIPS_RLD_MAP:
+ // Set the DT_MIPS_RLD_MAP entry to the address of _r_debug for GDB.
+ {
+ r_debug** dp = reinterpret_cast<r_debug**>(load_bias + d->d_un.d_ptr);
+ *dp = &_r_debug;
+ }
+ break;
+ case DT_MIPS_RLD_MAP_REL:
+ // Set the DT_MIPS_RLD_MAP_REL entry to the address of _r_debug for GDB.
+ {
+ r_debug** dp = reinterpret_cast<r_debug**>(
+ reinterpret_cast<ElfW(Addr)>(d) + d->d_un.d_val);
+ *dp = &_r_debug;
+ }
+ break;
+
+ case DT_MIPS_RLD_VERSION:
+ case DT_MIPS_FLAGS:
+ case DT_MIPS_BASE_ADDRESS:
+ case DT_MIPS_UNREFEXTNO:
+ break;
+
+ case DT_MIPS_SYMTABNO:
+ mips_symtabno_ = d->d_un.d_val;
+ break;
+
+ case DT_MIPS_LOCAL_GOTNO:
+ mips_local_gotno_ = d->d_un.d_val;
+ break;
+
+ case DT_MIPS_GOTSYM:
+ mips_gotsym_ = d->d_un.d_val;
+ break;
+#endif
+ // Ignored: "Its use has been superseded by the DF_BIND_NOW flag"
+ case DT_BIND_NOW:
+ break;
+
+ case DT_VERSYM:
+ versym_ = reinterpret_cast<ElfW(Versym)*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_VERDEF:
+ verdef_ptr_ = load_bias + d->d_un.d_ptr;
+ break;
+ case DT_VERDEFNUM:
+ verdef_cnt_ = d->d_un.d_val;
+ break;
+
+ case DT_VERNEED:
+ verneed_ptr_ = load_bias + d->d_un.d_ptr;
+ break;
+
+ case DT_VERNEEDNUM:
+ verneed_cnt_ = d->d_un.d_val;
+ break;
+
+ case DT_RUNPATH:
+ // this is parsed after we have strtab initialized (see below).
+ break;
+
+ default:
+ if (!relocating_linker) {
+ DL_WARN("%s: unused DT entry: type %p arg %p", get_realpath(),
+ reinterpret_cast<void*>(d->d_tag), reinterpret_cast<void*>(d->d_un.d_val));
+ }
+ break;
+ }
+ }
+
+#if defined(__mips__) && !defined(__LP64__)
+ if (!mips_check_and_adjust_fp_modes()) {
+ return false;
+ }
+#endif
+
+ DEBUG("si->base = %p, si->strtab = %p, si->symtab = %p",
+ reinterpret_cast<void*>(base), strtab_, symtab_);
+
+ // Sanity checks.
+ if (relocating_linker && needed_count != 0) {
+ DL_ERR("linker cannot have DT_NEEDED dependencies on other libraries");
+ return false;
+ }
+ if (nbucket_ == 0 && gnu_nbucket_ == 0) {
+ DL_ERR("empty/missing DT_HASH/DT_GNU_HASH in \"%s\" "
+ "(new hash type from the future?)", get_realpath());
+ return false;
+ }
+ if (strtab_ == 0) {
+ DL_ERR("empty/missing DT_STRTAB in \"%s\"", get_realpath());
+ return false;
+ }
+ if (symtab_ == 0) {
+ DL_ERR("empty/missing DT_SYMTAB in \"%s\"", get_realpath());
+ return false;
+ }
+
+ // second pass - parse entries relying on strtab
+ for (ElfW(Dyn)* d = dynamic; d->d_tag != DT_NULL; ++d) {
+ switch (d->d_tag) {
+ case DT_SONAME:
+ set_soname(get_string(d->d_un.d_val));
+ break;
+ case DT_RUNPATH:
+ set_dt_runpath(get_string(d->d_un.d_val));
+ break;
+ }
+ }
+
+ // Before M release linker was using basename in place of soname.
+ // In the case when dt_soname is absent some apps stop working
+ // because they can't find dt_needed library by soname.
+ // This workaround should keep them working. (applies only
+ // for apps targeting sdk version <=22). Make an exception for
+ // the main executable and linker; they do not need to have dt_soname
+ if (soname_ == nullptr && this != somain && (flags_ & FLAG_LINKER) == 0 &&
+ get_application_target_sdk_version() <= 22) {
+ soname_ = basename(realpath_.c_str());
+ DL_WARN("%s: is missing DT_SONAME will use basename as a replacement: \"%s\"",
+ get_realpath(), soname_);
+ // Don't call add_dlwarning because a missing DT_SONAME isn't important enough to show in the UI
+ }
+ return true;
+}
+
+bool soinfo::link_image(const soinfo_list_t& global_group, const soinfo_list_t& local_group,
+ const android_dlextinfo* extinfo) {
+
+ local_group_root_ = local_group.front();
+ if (local_group_root_ == nullptr) {
+ local_group_root_ = this;
+ }
+
+ if ((flags_ & FLAG_LINKER) == 0 && local_group_root_ == this) {
+ target_sdk_version_ = get_application_target_sdk_version();
+ }
+
+ VersionTracker version_tracker;
+
+ if (!version_tracker.init(this)) {
+ return false;
+ }
+
+#if !defined(__LP64__)
+ if (has_text_relocations) {
+ // Fail if app is targeting sdk version > 22
+ if (get_application_target_sdk_version() > 22) {
+ PRINT("%s: has text relocations", get_realpath());
+ DL_ERR("%s: has text relocations", get_realpath());
+ return false;
+ }
+ // Make segments writable to allow text relocations to work properly. We will later call
+ // phdr_table_protect_segments() after all of them are applied.
+ DL_WARN("%s has text relocations. This is wasting memory and prevents "
+ "security hardening. Please fix.", get_realpath());
+ add_dlwarning(get_realpath(), "text relocations");
+ if (phdr_table_unprotect_segments(phdr, phnum, load_bias) < 0) {
+ DL_ERR("can't unprotect loadable segments for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ }
+#endif
+
+ if (android_relocs_ != nullptr) {
+ // check signature
+ if (android_relocs_size_ > 3 &&
+ android_relocs_[0] == 'A' &&
+ android_relocs_[1] == 'P' &&
+ android_relocs_[2] == 'S' &&
+ android_relocs_[3] == '2') {
+ DEBUG("[ android relocating %s ]", get_realpath());
+
+ bool relocated = false;
+ const uint8_t* packed_relocs = android_relocs_ + 4;
+ const size_t packed_relocs_size = android_relocs_size_ - 4;
+
+ relocated = relocate(
+ version_tracker,
+ packed_reloc_iterator<sleb128_decoder>(
+ sleb128_decoder(packed_relocs, packed_relocs_size)),
+ global_group, local_group);
+
+ if (!relocated) {
+ return false;
+ }
+ } else {
+ DL_ERR("bad android relocation header.");
+ return false;
+ }
+ }
+
+#if defined(USE_RELA)
+ if (rela_ != nullptr) {
+ DEBUG("[ relocating %s ]", get_realpath());
+ if (!relocate(version_tracker,
+ plain_reloc_iterator(rela_, rela_count_), global_group, local_group)) {
+ return false;
+ }
+ }
+ if (plt_rela_ != nullptr) {
+ DEBUG("[ relocating %s plt ]", get_realpath());
+ if (!relocate(version_tracker,
+ plain_reloc_iterator(plt_rela_, plt_rela_count_), global_group, local_group)) {
+ return false;
+ }
+ }
+#else
+ if (rel_ != nullptr) {
+ DEBUG("[ relocating %s ]", get_realpath());
+ if (!relocate(version_tracker,
+ plain_reloc_iterator(rel_, rel_count_), global_group, local_group)) {
+ return false;
+ }
+ }
+ if (plt_rel_ != nullptr) {
+ DEBUG("[ relocating %s plt ]", get_realpath());
+ if (!relocate(version_tracker,
+ plain_reloc_iterator(plt_rel_, plt_rel_count_), global_group, local_group)) {
+ return false;
+ }
+ }
+#endif
+
+#if defined(__mips__)
+ if (!mips_relocate_got(version_tracker, global_group, local_group)) {
+ return false;
+ }
+#endif
+
+ DEBUG("[ finished linking %s ]", get_realpath());
+
+#if !defined(__LP64__)
+ if (has_text_relocations) {
+ // All relocations are done, we can protect our segments back to read-only.
+ if (phdr_table_protect_segments(phdr, phnum, load_bias) < 0) {
+ DL_ERR("can't protect segments for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ }
+#endif
+
+ // We can also turn on GNU RELRO protection if we're not linking the dynamic linker
+ // itself --- it can't make system calls yet, and will have to call protect_relro later.
+ if (!is_linker() && !protect_relro()) {
+ return false;
+ }
+
+ /* Handle serializing/sharing the RELRO segment */
+ if (extinfo && (extinfo->flags & ANDROID_DLEXT_WRITE_RELRO)) {
+ if (phdr_table_serialize_gnu_relro(phdr, phnum, load_bias,
+ extinfo->relro_fd) < 0) {
+ DL_ERR("failed serializing GNU RELRO section for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ } else if (extinfo && (extinfo->flags & ANDROID_DLEXT_USE_RELRO)) {
+ if (phdr_table_map_gnu_relro(phdr, phnum, load_bias,
+ extinfo->relro_fd) < 0) {
+ DL_ERR("failed mapping GNU RELRO section for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ }
+
+ notify_gdb_of_load(this);
+ return true;
+}
+
+bool soinfo::protect_relro() {
+ if (phdr_table_protect_gnu_relro(phdr, phnum, load_bias) < 0) {
+ DL_ERR("can't enable GNU RELRO protection for \"%s\": %s",
+ get_realpath(), strerror(errno));
+ return false;
+ }
+ return true;
+}
+
+/*
+ * This function add vdso to internal dso list.
+ * It helps to stack unwinding through signal handlers.
+ * Also, it makes bionic more like glibc.
+ */
+static void add_vdso(KernelArgumentBlock& args __unused) {
+#if defined(AT_SYSINFO_EHDR)
+ ElfW(Ehdr)* ehdr_vdso = reinterpret_cast<ElfW(Ehdr)*>(args.getauxval(AT_SYSINFO_EHDR));
+ if (ehdr_vdso == nullptr) {
+ return;
+ }
+
+ soinfo* si = soinfo_alloc(&g_default_namespace, "[vdso]", nullptr, 0, 0);
+
+ si->phdr = reinterpret_cast<ElfW(Phdr)*>(reinterpret_cast<char*>(ehdr_vdso) + ehdr_vdso->e_phoff);
+ si->phnum = ehdr_vdso->e_phnum;
+ si->base = reinterpret_cast<ElfW(Addr)>(ehdr_vdso);
+ si->size = phdr_table_get_load_size(si->phdr, si->phnum);
+ si->load_bias = get_elf_exec_load_bias(ehdr_vdso);
+
+ si->prelink_image();
+ si->link_image(g_empty_list, soinfo_list_t::make_list(si), nullptr);
+#endif
+}
+
+/* gdb expects the linker to be in the debug shared object list.
+ * Without this, gdb has trouble locating the linker's ".text"
+ * and ".plt" sections. Gdb could also potentially use this to
+ * relocate the offset of our exported 'rtld_db_dlactivity' symbol.
+ * Note that the linker shouldn't be on the soinfo list.
+ */
+static void init_linker_info_for_gdb(ElfW(Addr) linker_base) {
+ static link_map linker_link_map_for_gdb;
+#if defined(__LP64__)
+ static char kLinkerPath[] = "/system/bin/linker64";
+#else
+ static char kLinkerPath[] = "/system/bin/linker";
+#endif
+
+ linker_link_map_for_gdb.l_addr = linker_base;
+ linker_link_map_for_gdb.l_name = kLinkerPath;
+
+ /*
+ * Set the dynamic field in the link map otherwise gdb will complain with
+ * the following:
+ * warning: .dynamic section for "/system/bin/linker" is not at the
+ * expected address (wrong library or version mismatch?)
+ */
+ ElfW(Ehdr)* elf_hdr = reinterpret_cast<ElfW(Ehdr)*>(linker_base);
+ ElfW(Phdr)* phdr = reinterpret_cast<ElfW(Phdr)*>(linker_base + elf_hdr->e_phoff);
+ phdr_table_get_dynamic_section(phdr, elf_hdr->e_phnum, linker_base,
+ &linker_link_map_for_gdb.l_ld, nullptr);
+
+ insert_link_map_into_debug_map(&linker_link_map_for_gdb);
+}
+
+static void init_default_namespace() {
+ g_default_namespace.set_name("(default)");
+ g_default_namespace.set_isolated(false);
+
+ const char *interp = phdr_table_get_interpreter_name(somain->phdr, somain->phnum,
+ somain->load_bias);
+ const char* bname = basename(interp);
+ if (bname && (strcmp(bname, "linker_asan") == 0 || strcmp(bname, "linker_asan64") == 0)) {
+ g_default_ld_paths = kAsanDefaultLdPaths;
+ g_is_asan = true;
+ } else {
+ g_default_ld_paths = kDefaultLdPaths;
+ }
+
+ std::vector<std::string> ld_default_paths;
+ for (size_t i = 0; g_default_ld_paths[i] != nullptr; ++i) {
+ ld_default_paths.push_back(g_default_ld_paths[i]);
+ }
+
+ g_default_namespace.set_default_library_paths(std::move(ld_default_paths));
+};
+
+extern "C" int __system_properties_init(void);
+
+static const char* get_executable_path() {
+ static std::string executable_path;
+ if (executable_path.empty()) {
+ char path[PATH_MAX];
+ ssize_t path_len = readlink("/proc/self/exe", path, sizeof(path));
+ if (path_len == -1 || path_len >= static_cast<ssize_t>(sizeof(path))) {
+ __libc_fatal("readlink('/proc/self/exe') failed: %s", strerror(errno));
+ }
+ executable_path = std::string(path, path_len);
+ }
+
+ return executable_path.c_str();
+}
+
+/*
+ * This code is called after the linker has linked itself and
+ * fixed it's own GOT. It is safe to make references to externs
+ * and other non-local data at this point.
+ */
+static ElfW(Addr) __linker_init_post_relocation(KernelArgumentBlock& args, ElfW(Addr) linker_base) {
+#if TIMING
+ struct timeval t0, t1;
+ gettimeofday(&t0, 0);
+#endif
+
+ // Sanitize the environment.
+ __libc_init_AT_SECURE(args);
+
+ // Initialize system properties
+ __system_properties_init(); // may use 'environ'
+
+ // Register the debuggerd signal handler.
+ debuggerd_callbacks_t callbacks = {
+ .get_abort_message = []() {
+ return g_abort_message;
+ },
+ .post_dump = ¬ify_gdb_of_libraries,
+ };
+ debuggerd_init(&callbacks);
+
+ g_linker_logger.ResetState();
+
+ // Get a few environment variables.
+ const char* LD_DEBUG = getenv("LD_DEBUG");
+ if (LD_DEBUG != nullptr) {
+ g_ld_debug_verbosity = atoi(LD_DEBUG);
+ }
+
+#if defined(__LP64__)
+ INFO("[ Android dynamic linker (64-bit) ]");
+#else
+ INFO("[ Android dynamic linker (32-bit) ]");
+#endif
+
+ // These should have been sanitized by __libc_init_AT_SECURE, but the test
+ // doesn't cost us anything.
+ const char* ldpath_env = nullptr;
+ const char* ldpreload_env = nullptr;
+ if (!getauxval(AT_SECURE)) {
+ ldpath_env = getenv("LD_LIBRARY_PATH");
+ if (ldpath_env != nullptr) {
+ INFO("[ LD_LIBRARY_PATH set to \"%s\" ]", ldpath_env);
+ }
+ ldpreload_env = getenv("LD_PRELOAD");
+ if (ldpreload_env != nullptr) {
+ INFO("[ LD_PRELOAD set to \"%s\" ]", ldpreload_env);
+ }
+ }
+
+ const char* executable_path = get_executable_path();
+ struct stat file_stat;
+ if (TEMP_FAILURE_RETRY(stat(executable_path, &file_stat)) != 0) {
+ __libc_fatal("unable to stat file for the executable \"%s\": %s", executable_path, strerror(errno));
+ }
+
+ soinfo* si = soinfo_alloc(&g_default_namespace, executable_path, &file_stat, 0, RTLD_GLOBAL);
+ if (si == nullptr) {
+ __libc_fatal("Couldn't allocate soinfo: out of memory?");
+ }
+
+ /* bootstrap the link map, the main exe always needs to be first */
+ si->set_main_executable();
+ link_map* map = &(si->link_map_head);
+
+ // Register the main executable and the linker upfront to have
+ // gdb aware of them before loading the rest of the dependency
+ // tree.
+ map->l_addr = 0;
+ map->l_name = const_cast<char*>(executable_path);
+ insert_link_map_into_debug_map(map);
+ init_linker_info_for_gdb(linker_base);
+
+ // Extract information passed from the kernel.
+ si->phdr = reinterpret_cast<ElfW(Phdr)*>(args.getauxval(AT_PHDR));
+ si->phnum = args.getauxval(AT_PHNUM);
+
+ /* Compute the value of si->base. We can't rely on the fact that
+ * the first entry is the PHDR because this will not be true
+ * for certain executables (e.g. some in the NDK unit test suite)
+ */
+ si->base = 0;
+ si->size = phdr_table_get_load_size(si->phdr, si->phnum);
+ si->load_bias = 0;
+ for (size_t i = 0; i < si->phnum; ++i) {
+ if (si->phdr[i].p_type == PT_PHDR) {
+ si->load_bias = reinterpret_cast<ElfW(Addr)>(si->phdr) - si->phdr[i].p_vaddr;
+ si->base = reinterpret_cast<ElfW(Addr)>(si->phdr) - si->phdr[i].p_offset;
+ break;
+ }
+ }
+ si->dynamic = nullptr;
+
+ ElfW(Ehdr)* elf_hdr = reinterpret_cast<ElfW(Ehdr)*>(si->base);
+ if (elf_hdr->e_type != ET_DYN) {
+ __libc_fatal("\"%s\": error: only position independent executables (PIE) are supported.",
+ g_argv[0]);
+ }
+
+ // Use LD_LIBRARY_PATH and LD_PRELOAD (but only if we aren't setuid/setgid).
+ parse_LD_LIBRARY_PATH(ldpath_env);
+ parse_LD_PRELOAD(ldpreload_env);
+
+ somain = si;
+
+ init_default_namespace();
+
+ if (!si->prelink_image()) {
+ __libc_fatal("CANNOT LINK EXECUTABLE \"%s\": %s", g_argv[0], linker_get_error_buffer());
+ }
+
+ // add somain to global group
+ si->set_dt_flags_1(si->get_dt_flags_1() | DF_1_GLOBAL);
+
+ // Load ld_preloads and dependencies.
+ StringLinkedList needed_library_name_list;
+ size_t needed_libraries_count = 0;
+ size_t ld_preloads_count = 0;
+
+ for (const auto& ld_preload_name : g_ld_preload_names) {
+ needed_library_name_list.push_back(ld_preload_name.c_str());
+ ++needed_libraries_count;
+ ++ld_preloads_count;
+ }
+
+ for_each_dt_needed(si, [&](const char* name) {
+ needed_library_name_list.push_back(name);
+ ++needed_libraries_count;
+ });
+
+ const char* needed_library_names[needed_libraries_count];
+
+ memset(needed_library_names, 0, sizeof(needed_library_names));
+ needed_library_name_list.copy_to_array(needed_library_names, needed_libraries_count);
+
+ if (needed_libraries_count > 0 &&
+ !find_libraries(&g_default_namespace, si, needed_library_names, needed_libraries_count,
+ nullptr, &g_ld_preloads, ld_preloads_count, RTLD_GLOBAL, nullptr,
+ /* add_as_children */ true)) {
+ __libc_fatal("CANNOT LINK EXECUTABLE \"%s\": %s", g_argv[0], linker_get_error_buffer());
+ } else if (needed_libraries_count == 0) {
+ if (!si->link_image(g_empty_list, soinfo_list_t::make_list(si), nullptr)) {
+ __libc_fatal("CANNOT LINK EXECUTABLE \"%s\": %s", g_argv[0], linker_get_error_buffer());
+ }
+ si->increment_ref_count();
+ }
+
+ add_vdso(args);
+
+ {
+ ProtectedDataGuard guard;
+
+ si->call_pre_init_constructors();
+
+ /* After the prelink_image, the si->load_bias is initialized.
+ * For so lib, the map->l_addr will be updated in notify_gdb_of_load.
+ * We need to update this value for so exe here. So Unwind_Backtrace
+ * for some arch like x86 could work correctly within so exe.
+ */
+ map->l_addr = si->load_bias;
+ si->call_constructors();
+ }
+
+#if TIMING
+ gettimeofday(&t1, nullptr);
+ PRINT("LINKER TIME: %s: %d microseconds", g_argv[0], (int) (
+ (((long long)t1.tv_sec * 1000000LL) + (long long)t1.tv_usec) -
+ (((long long)t0.tv_sec * 1000000LL) + (long long)t0.tv_usec)));
+#endif
+#if STATS
+ PRINT("RELO STATS: %s: %d abs, %d rel, %d copy, %d symbol", g_argv[0],
+ linker_stats.count[kRelocAbsolute],
+ linker_stats.count[kRelocRelative],
+ linker_stats.count[kRelocCopy],
+ linker_stats.count[kRelocSymbol]);
+#endif
+#if COUNT_PAGES
+ {
+ unsigned n;
+ unsigned i;
+ unsigned count = 0;
+ for (n = 0; n < 4096; n++) {
+ if (bitmask[n]) {
+ unsigned x = bitmask[n];
+#if defined(__LP64__)
+ for (i = 0; i < 32; i++) {
+#else
+ for (i = 0; i < 8; i++) {
+#endif
+ if (x & 1) {
+ count++;
+ }
+ x >>= 1;
+ }
+ }
+ }
+ PRINT("PAGES MODIFIED: %s: %d (%dKB)", g_argv[0], count, count * 4);
+ }
+#endif
+
+#if TIMING || STATS || COUNT_PAGES
+ fflush(stdout);
+#endif
+
+ ElfW(Addr) entry = args.getauxval(AT_ENTRY);
+ TRACE("[ Ready to execute \"%s\" @ %p ]", si->get_realpath(), reinterpret_cast<void*>(entry));
+ return entry;
+}
+
+/* Compute the load-bias of an existing executable. This shall only
+ * be used to compute the load bias of an executable or shared library
+ * that was loaded by the kernel itself.
+ *
+ * Input:
+ * elf -> address of ELF header, assumed to be at the start of the file.
+ * Return:
+ * load bias, i.e. add the value of any p_vaddr in the file to get
+ * the corresponding address in memory.
+ */
+static ElfW(Addr) get_elf_exec_load_bias(const ElfW(Ehdr)* elf) {
+ ElfW(Addr) offset = elf->e_phoff;
+ const ElfW(Phdr)* phdr_table =
+ reinterpret_cast<const ElfW(Phdr)*>(reinterpret_cast<uintptr_t>(elf) + offset);
+ const ElfW(Phdr)* phdr_end = phdr_table + elf->e_phnum;
+
+ for (const ElfW(Phdr)* phdr = phdr_table; phdr < phdr_end; phdr++) {
+ if (phdr->p_type == PT_LOAD) {
+ return reinterpret_cast<ElfW(Addr)>(elf) + phdr->p_offset - phdr->p_vaddr;
+ }
+ }
+ return 0;
+}
+
+static void __linker_cannot_link(const char* argv0) {
+ __libc_fatal("CANNOT LINK EXECUTABLE \"%s\": %s", argv0, linker_get_error_buffer());
+}
+
+/*
+ * This is the entry point for the linker, called from begin.S. This
+ * method is responsible for fixing the linker's own relocations, and
+ * then calling __linker_init_post_relocation().
+ *
+ * Because this method is called before the linker has fixed it's own
+ * relocations, any attempt to reference an extern variable, extern
+ * function, or other GOT reference will generate a segfault.
+ */
+extern "C" ElfW(Addr) __linker_init(void* raw_args) {
+ KernelArgumentBlock args(raw_args);
+
+ ElfW(Addr) linker_addr = args.getauxval(AT_BASE);
+ ElfW(Addr) entry_point = args.getauxval(AT_ENTRY);
+ ElfW(Ehdr)* elf_hdr = reinterpret_cast<ElfW(Ehdr)*>(linker_addr);
+ ElfW(Phdr)* phdr = reinterpret_cast<ElfW(Phdr)*>(linker_addr + elf_hdr->e_phoff);
+
+ soinfo linker_so(nullptr, nullptr, nullptr, 0, 0);
+
+ // If the linker is not acting as PT_INTERP entry_point is equal to
+ // _start. Which means that the linker is running as an executable and
+ // already linked by PT_INTERP.
+ //
+ // This happens when user tries to run 'adb shell /system/bin/linker'
+ // see also https://code.google.com/p/android/issues/detail?id=63174
+ if (reinterpret_cast<ElfW(Addr)>(&_start) == entry_point) {
+ __libc_format_fd(STDOUT_FILENO,
+ "This is %s, the helper program for shared library executables.\n",
+ args.argv[0]);
+ exit(0);
+ }
+
+ linker_so.base = linker_addr;
+ linker_so.size = phdr_table_get_load_size(phdr, elf_hdr->e_phnum);
+ linker_so.load_bias = get_elf_exec_load_bias(elf_hdr);
+ linker_so.dynamic = nullptr;
+ linker_so.phdr = phdr;
+ linker_so.phnum = elf_hdr->e_phnum;
+ linker_so.set_linker_flag();
+
+ // Prelink the linker so we can access linker globals.
+ if (!linker_so.prelink_image()) __linker_cannot_link(args.argv[0]);
+
+ // This might not be obvious... The reasons why we pass g_empty_list
+ // in place of local_group here are (1) we do not really need it, because
+ // linker is built with DT_SYMBOLIC and therefore relocates its symbols against
+ // itself without having to look into local_group and (2) allocators
+ // are not yet initialized, and therefore we cannot use linked_list.push_*
+ // functions at this point.
+ if (!linker_so.link_image(g_empty_list, g_empty_list, nullptr)) __linker_cannot_link(args.argv[0]);
+
+#if defined(__i386__)
+ // On x86, we can't make system calls before this point.
+ // We can't move this up because this needs to assign to a global.
+ // Note that until we call __libc_init_main_thread below we have
+ // no TLS, so you shouldn't make a system call that can fail, because
+ // it will SEGV when it tries to set errno.
+ __libc_init_sysinfo(args);
+#endif
+
+ // Initialize the main thread (including TLS, so system calls really work).
+ __libc_init_main_thread(args);
+
+ // We didn't protect the linker's RELRO pages in link_image because we
+ // couldn't make system calls on x86 at that point, but we can now...
+ if (!linker_so.protect_relro()) __linker_cannot_link(args.argv[0]);
+
+ // Initialize the linker's static libc's globals
+ __libc_init_globals(args);
+
+ // store argc/argv/envp to use them for calling constructors
+ g_argc = args.argc;
+ g_argv = args.argv;
+ g_envp = args.envp;
+
+ // Initialize the linker's own global variables
+ linker_so.call_constructors();
+
+ // Initialize static variables. Note that in order to
+ // get correct libdl_info we need to call constructors
+ // before get_libdl_info().
+ solist = get_libdl_info();
+ sonext = get_libdl_info();
+ g_default_namespace.add_soinfo(get_libdl_info());
+
+ // We have successfully fixed our own relocations. It's safe to run
+ // the main part of the linker now.
+ args.abort_message_ptr = &g_abort_message;
+ ElfW(Addr) start_address = __linker_init_post_relocation(args, linker_addr);
+
+ INFO("[ Jumping to _start (%p)... ]", reinterpret_cast<void*>(start_address));
+
+ // Return the address that the calling assembly stub should jump to.
+ return start_address;
+}
diff --git a/linker/linker.h b/linker/linker.h
new file mode 100644
index 0000000..4787471
--- /dev/null
+++ b/linker/linker.h
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _LINKER_H_
+#define _LINKER_H_
+
+#include <dlfcn.h>
+#include <android/dlext.h>
+#include <elf.h>
+#include <inttypes.h>
+#include <link.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "private/bionic_page.h"
+#include "private/libc_logging.h"
+#include "linked_list.h"
+#include "linker_common_types.h"
+#include "linker_logger.h"
+#include "linker_soinfo.h"
+
+#include <string>
+#include <vector>
+
+#if defined(__LP64__)
+#define ELFW(what) ELF64_ ## what
+#else
+#define ELFW(what) ELF32_ ## what
+#endif
+
+// mips64 interprets Elf64_Rel structures' r_info field differently.
+// bionic (like other C libraries) has macros that assume regular ELF files,
+// but the dynamic linker needs to be able to load mips64 ELF files.
+#if defined(__mips__) && defined(__LP64__)
+#undef ELF64_R_SYM
+#undef ELF64_R_TYPE
+#undef ELF64_R_INFO
+#define ELF64_R_SYM(info) (((info) >> 0) & 0xffffffff)
+#define ELF64_R_SSYM(info) (((info) >> 32) & 0xff)
+#define ELF64_R_TYPE3(info) (((info) >> 40) & 0xff)
+#define ELF64_R_TYPE2(info) (((info) >> 48) & 0xff)
+#define ELF64_R_TYPE(info) (((info) >> 56) & 0xff)
+#endif
+
+#define SUPPORTED_DT_FLAGS_1 (DF_1_NOW | DF_1_GLOBAL | DF_1_NODELETE | DF_1_PIE)
+
+// Class used construct version dependency graph.
+class VersionTracker {
+ public:
+ VersionTracker() = default;
+ bool init(const soinfo* si_from);
+
+ const version_info* get_version_info(ElfW(Versym) source_symver) const;
+ private:
+ bool init_verneed(const soinfo* si_from);
+ bool init_verdef(const soinfo* si_from);
+ void add_version_info(size_t source_index, ElfW(Word) elf_hash,
+ const char* ver_name, const soinfo* target_si);
+
+ std::vector<version_info> version_infos;
+
+ DISALLOW_COPY_AND_ASSIGN(VersionTracker);
+};
+
+bool soinfo_do_lookup(soinfo* si_from, const char* name, const version_info* vi,
+ soinfo** si_found_in, const soinfo_list_t& global_group,
+ const soinfo_list_t& local_group, const ElfW(Sym)** symbol);
+
+enum RelocationKind {
+ kRelocAbsolute = 0,
+ kRelocRelative,
+ kRelocCopy,
+ kRelocSymbol,
+ kRelocMax
+};
+
+void count_relocation(RelocationKind kind);
+
+soinfo* get_libdl_info();
+
+void do_android_get_LD_LIBRARY_PATH(char*, size_t);
+void do_android_update_LD_LIBRARY_PATH(const char* ld_library_path);
+void* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo, void* caller_addr);
+int do_dlclose(void* handle);
+
+int do_dl_iterate_phdr(int (*cb)(dl_phdr_info* info, size_t size, void* data), void* data);
+
+bool do_dlsym(void* handle, const char* sym_name, const char* sym_ver,
+ void* caller_addr, void** symbol);
+
+int do_dladdr(const void* addr, Dl_info* info);
+
+void set_application_target_sdk_version(uint32_t target);
+uint32_t get_application_target_sdk_version();
+
+enum {
+ /* A regular namespace is the namespace with a custom search path that does
+ * not impose any restrictions on the location of native libraries.
+ */
+ ANDROID_NAMESPACE_TYPE_REGULAR = 0,
+
+ /* An isolated namespace requires all the libraries to be on the search path
+ * or under permitted_when_isolated_path. The search path is the union of
+ * ld_library_path and default_library_path.
+ */
+ ANDROID_NAMESPACE_TYPE_ISOLATED = 1,
+
+ /* The shared namespace clones the list of libraries of the caller namespace upon creation
+ * which means that they are shared between namespaces - the caller namespace and the new one
+ * will use the same copy of a library if it was loaded prior to android_create_namespace call.
+ *
+ * Note that libraries loaded after the namespace is created will not be shared.
+ *
+ * Shared namespaces can be isolated or regular. Note that they do not inherit the search path nor
+ * permitted_path from the caller's namespace.
+ */
+ ANDROID_NAMESPACE_TYPE_SHARED = 2,
+ ANDROID_NAMESPACE_TYPE_SHARED_ISOLATED = ANDROID_NAMESPACE_TYPE_SHARED |
+ ANDROID_NAMESPACE_TYPE_ISOLATED,
+};
+
+bool init_namespaces(const char* public_ns_sonames, const char* anon_ns_library_path);
+android_namespace_t* create_namespace(const void* caller_addr,
+ const char* name,
+ const char* ld_library_path,
+ const char* default_library_path,
+ uint64_t type,
+ const char* permitted_when_isolated_path,
+ android_namespace_t* parent_namespace);
+
+constexpr unsigned kLibraryAlignmentBits = 18;
+constexpr size_t kLibraryAlignment = 1UL << kLibraryAlignmentBits;
+
+#endif
diff --git a/linker/linker_allocator.cpp b/linker/linker_allocator.cpp
new file mode 100644
index 0000000..dc6dfc1
--- /dev/null
+++ b/linker/linker_allocator.cpp
@@ -0,0 +1,345 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker_allocator.h"
+#include "linker_debug.h"
+#include "linker.h"
+
+#include <algorithm>
+#include <vector>
+
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include "private/bionic_prctl.h"
+
+//
+// LinkerMemeoryAllocator is general purpose allocator
+// designed to provide the same functionality as the malloc/free/realloc
+// libc functions.
+//
+// On alloc:
+// If size is >= 1k allocator proxies malloc call directly to mmap
+// If size < 1k allocator uses SmallObjectAllocator for the size
+// rounded up to the nearest power of two.
+//
+// On free:
+//
+// For a pointer allocated using proxy-to-mmap allocator unmaps
+// the memory.
+//
+// For a pointer allocated using SmallObjectAllocator it adds
+// the block to free_blocks_list_. If the number of free pages reaches 2,
+// SmallObjectAllocator munmaps one of the pages keeping the other one
+// in reserve.
+
+static const char kSignature[4] = {'L', 'M', 'A', 1};
+
+static const size_t kSmallObjectMaxSize = 1 << kSmallObjectMaxSizeLog2;
+
+// This type is used for large allocations (with size >1k)
+static const uint32_t kLargeObject = 111;
+
+bool operator<(const small_object_page_record& one, const small_object_page_record& two) {
+ return one.page_addr < two.page_addr;
+}
+
+static inline uint16_t log2(size_t number) {
+ uint16_t result = 0;
+ number--;
+
+ while (number != 0) {
+ result++;
+ number >>= 1;
+ }
+
+ return result;
+}
+
+LinkerSmallObjectAllocator::LinkerSmallObjectAllocator(uint32_t type, size_t block_size)
+ : type_(type), block_size_(block_size), free_pages_cnt_(0), free_blocks_list_(nullptr) {}
+
+void* LinkerSmallObjectAllocator::alloc() {
+ CHECK(block_size_ != 0);
+
+ if (free_blocks_list_ == nullptr) {
+ alloc_page();
+ }
+
+ small_object_block_record* block_record = free_blocks_list_;
+ if (block_record->free_blocks_cnt > 1) {
+ small_object_block_record* next_free = reinterpret_cast<small_object_block_record*>(
+ reinterpret_cast<uint8_t*>(block_record) + block_size_);
+ next_free->next = block_record->next;
+ next_free->free_blocks_cnt = block_record->free_blocks_cnt - 1;
+ free_blocks_list_ = next_free;
+ } else {
+ free_blocks_list_ = block_record->next;
+ }
+
+ // bookkeeping...
+ auto page_record = find_page_record(block_record);
+
+ if (page_record->allocated_blocks_cnt == 0) {
+ free_pages_cnt_--;
+ }
+
+ page_record->free_blocks_cnt--;
+ page_record->allocated_blocks_cnt++;
+
+ memset(block_record, 0, block_size_);
+
+ return block_record;
+}
+
+void LinkerSmallObjectAllocator::free_page(linker_vector_t::iterator page_record) {
+ void* page_start = reinterpret_cast<void*>(page_record->page_addr);
+ void* page_end = reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(page_start) + PAGE_SIZE);
+
+ while (free_blocks_list_ != nullptr &&
+ free_blocks_list_ > page_start &&
+ free_blocks_list_ < page_end) {
+ free_blocks_list_ = free_blocks_list_->next;
+ }
+
+ small_object_block_record* current = free_blocks_list_;
+
+ while (current != nullptr) {
+ while (current->next > page_start && current->next < page_end) {
+ current->next = current->next->next;
+ }
+
+ current = current->next;
+ }
+
+ munmap(page_start, PAGE_SIZE);
+ page_records_.erase(page_record);
+ free_pages_cnt_--;
+}
+
+void LinkerSmallObjectAllocator::free(void* ptr) {
+ auto page_record = find_page_record(ptr);
+
+ ssize_t offset = reinterpret_cast<uintptr_t>(ptr) - sizeof(page_info);
+
+ if (offset % block_size_ != 0) {
+ __libc_fatal("invalid pointer: %p (block_size=%zd)", ptr, block_size_);
+ }
+
+ memset(ptr, 0, block_size_);
+ small_object_block_record* block_record = reinterpret_cast<small_object_block_record*>(ptr);
+
+ block_record->next = free_blocks_list_;
+ block_record->free_blocks_cnt = 1;
+
+ free_blocks_list_ = block_record;
+
+ page_record->free_blocks_cnt++;
+ page_record->allocated_blocks_cnt--;
+
+ if (page_record->allocated_blocks_cnt == 0) {
+ if (free_pages_cnt_++ > 1) {
+ // if we already have a free page - unmap this one.
+ free_page(page_record);
+ }
+ }
+}
+
+linker_vector_t::iterator LinkerSmallObjectAllocator::find_page_record(void* ptr) {
+ void* addr = reinterpret_cast<void*>(PAGE_START(reinterpret_cast<uintptr_t>(ptr)));
+ small_object_page_record boundary;
+ boundary.page_addr = addr;
+ linker_vector_t::iterator it = std::lower_bound(
+ page_records_.begin(), page_records_.end(), boundary);
+
+ if (it == page_records_.end() || it->page_addr != addr) {
+ // not found...
+ __libc_fatal("page record for %p was not found (block_size=%zd)", ptr, block_size_);
+ }
+
+ return it;
+}
+
+void LinkerSmallObjectAllocator::create_page_record(void* page_addr, size_t free_blocks_cnt) {
+ small_object_page_record record;
+ record.page_addr = page_addr;
+ record.free_blocks_cnt = free_blocks_cnt;
+ record.allocated_blocks_cnt = 0;
+
+ linker_vector_t::iterator it = std::lower_bound(
+ page_records_.begin(), page_records_.end(), record);
+ page_records_.insert(it, record);
+}
+
+void LinkerSmallObjectAllocator::alloc_page() {
+ static_assert(sizeof(page_info) % 16 == 0,
+ "sizeof(page_info) is not multiple of 16");
+ void* map_ptr = mmap(nullptr, PAGE_SIZE,
+ PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
+ if (map_ptr == MAP_FAILED) {
+ __libc_fatal("mmap failed");
+ }
+
+ prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, map_ptr, PAGE_SIZE, "linker_alloc_small_objects");
+
+ memset(map_ptr, 0, PAGE_SIZE);
+
+ page_info* info = reinterpret_cast<page_info*>(map_ptr);
+ memcpy(info->signature, kSignature, sizeof(kSignature));
+ info->type = type_;
+ info->allocator_addr = this;
+
+ size_t free_blocks_cnt = (PAGE_SIZE - sizeof(page_info))/block_size_;
+
+ create_page_record(map_ptr, free_blocks_cnt);
+
+ small_object_block_record* first_block = reinterpret_cast<small_object_block_record*>(info + 1);
+
+ first_block->next = free_blocks_list_;
+ first_block->free_blocks_cnt = free_blocks_cnt;
+
+ free_blocks_list_ = first_block;
+}
+
+
+void LinkerMemoryAllocator::initialize_allocators() {
+ if (allocators_ != nullptr) {
+ return;
+ }
+
+ LinkerSmallObjectAllocator* allocators =
+ reinterpret_cast<LinkerSmallObjectAllocator*>(allocators_buf_);
+
+ for (size_t i = 0; i < kSmallObjectAllocatorsCount; ++i) {
+ uint32_t type = i + kSmallObjectMinSizeLog2;
+ new (allocators + i) LinkerSmallObjectAllocator(type, 1 << type);
+ }
+
+ allocators_ = allocators;
+}
+
+void* LinkerMemoryAllocator::alloc_mmap(size_t size) {
+ size_t allocated_size = PAGE_END(size + sizeof(page_info));
+ void* map_ptr = mmap(nullptr, allocated_size,
+ PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
+
+ if (map_ptr == MAP_FAILED) {
+ __libc_fatal("mmap failed");
+ }
+
+ prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, map_ptr, allocated_size, "linker_alloc_lob");
+
+ memset(map_ptr, 0, allocated_size);
+
+ page_info* info = reinterpret_cast<page_info*>(map_ptr);
+ memcpy(info->signature, kSignature, sizeof(kSignature));
+ info->type = kLargeObject;
+ info->allocated_size = allocated_size;
+
+ return info + 1;
+}
+
+void* LinkerMemoryAllocator::alloc(size_t size) {
+ // treat alloc(0) as alloc(1)
+ if (size == 0) {
+ size = 1;
+ }
+
+ if (size > kSmallObjectMaxSize) {
+ return alloc_mmap(size);
+ }
+
+ uint16_t log2_size = log2(size);
+
+ if (log2_size < kSmallObjectMinSizeLog2) {
+ log2_size = kSmallObjectMinSizeLog2;
+ }
+
+ return get_small_object_allocator(log2_size)->alloc();
+}
+
+page_info* LinkerMemoryAllocator::get_page_info(void* ptr) {
+ page_info* info = reinterpret_cast<page_info*>(PAGE_START(reinterpret_cast<size_t>(ptr)));
+ if (memcmp(info->signature, kSignature, sizeof(kSignature)) != 0) {
+ __libc_fatal("invalid pointer %p (page signature mismatch)", ptr);
+ }
+
+ return info;
+}
+
+void* LinkerMemoryAllocator::realloc(void* ptr, size_t size) {
+ if (ptr == nullptr) {
+ return alloc(size);
+ }
+
+ if (size == 0) {
+ free(ptr);
+ return nullptr;
+ }
+
+ page_info* info = get_page_info(ptr);
+
+ size_t old_size = 0;
+
+ if (info->type == kLargeObject) {
+ old_size = info->allocated_size - sizeof(page_info);
+ } else {
+ LinkerSmallObjectAllocator* allocator = get_small_object_allocator(info->type);
+ if (allocator != info->allocator_addr) {
+ __libc_fatal("invalid pointer %p (page signature mismatch)", ptr);
+ }
+
+ old_size = allocator->get_block_size();
+ }
+
+ if (old_size < size) {
+ void *result = alloc(size);
+ memcpy(result, ptr, old_size);
+ free(ptr);
+ return result;
+ }
+
+ return ptr;
+}
+
+void LinkerMemoryAllocator::free(void* ptr) {
+ if (ptr == nullptr) {
+ return;
+ }
+
+ page_info* info = get_page_info(ptr);
+
+ if (info->type == kLargeObject) {
+ munmap(info, info->allocated_size);
+ } else {
+ LinkerSmallObjectAllocator* allocator = get_small_object_allocator(info->type);
+ if (allocator != info->allocator_addr) {
+ __libc_fatal("invalid pointer %p (invalid allocator address for the page)", ptr);
+ }
+
+ allocator->free(ptr);
+ }
+}
+
+LinkerSmallObjectAllocator* LinkerMemoryAllocator::get_small_object_allocator(uint32_t type) {
+ if (type < kSmallObjectMinSizeLog2 || type > kSmallObjectMaxSizeLog2) {
+ __libc_fatal("invalid type: %u", type);
+ }
+
+ initialize_allocators();
+ return &allocators_[type - kSmallObjectMinSizeLog2];
+}
diff --git a/linker/linker_allocator.h b/linker/linker_allocator.h
new file mode 100644
index 0000000..8f90dbf
--- /dev/null
+++ b/linker/linker_allocator.h
@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LINKER_ALLOCATOR_H
+#define __LINKER_ALLOCATOR_H
+
+#include <stdlib.h>
+#include <sys/cdefs.h>
+#include <sys/mman.h>
+#include <stddef.h>
+#include <unistd.h>
+
+#include <vector>
+
+#include "private/bionic_prctl.h"
+#include "private/libc_logging.h"
+
+const uint32_t kSmallObjectMaxSizeLog2 = 10;
+const uint32_t kSmallObjectMinSizeLog2 = 4;
+const uint32_t kSmallObjectAllocatorsCount = kSmallObjectMaxSizeLog2 - kSmallObjectMinSizeLog2 + 1;
+
+class LinkerSmallObjectAllocator;
+
+// This structure is placed at the beginning of each addressable page
+// and has all information we need to find the corresponding memory allocator.
+struct page_info {
+ char signature[4];
+ uint32_t type;
+ union {
+ // we use allocated_size for large objects allocator
+ size_t allocated_size;
+ // and allocator_addr for small ones.
+ LinkerSmallObjectAllocator* allocator_addr;
+ };
+} __attribute__((aligned(16)));
+
+struct small_object_page_record {
+ void* page_addr;
+ size_t free_blocks_cnt;
+ size_t allocated_blocks_cnt;
+};
+
+// for lower_bound...
+bool operator<(const small_object_page_record& one, const small_object_page_record& two);
+
+struct small_object_block_record {
+ small_object_block_record* next;
+ size_t free_blocks_cnt;
+};
+
+// This is implementation for std::vector allocator
+template <typename T>
+class linker_vector_allocator {
+ public:
+ typedef T value_type;
+ typedef T* pointer;
+ typedef const T* const_pointer;
+ typedef T& reference;
+ typedef const T& const_reference;
+ typedef size_t size_type;
+ typedef ptrdiff_t difference_type;
+
+ T* allocate(size_t n, const T* hint = nullptr) {
+ size_t size = n * sizeof(T);
+ void* ptr = mmap(const_cast<T*>(hint), size,
+ PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
+ if (ptr == MAP_FAILED) {
+ // Spec says we need to throw std::bad_alloc here but because our
+ // code does not support exception handling anyways - we are going to abort.
+ __libc_fatal("mmap failed");
+ }
+
+ prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, ptr, size, "linker_alloc_vector");
+
+ return reinterpret_cast<T*>(ptr);
+ }
+
+ void deallocate(T* ptr, size_t n) {
+ munmap(ptr, n * sizeof(T));
+ }
+};
+
+typedef
+ std::vector<small_object_page_record, linker_vector_allocator<small_object_page_record>>
+ linker_vector_t;
+
+
+class LinkerSmallObjectAllocator {
+ public:
+ LinkerSmallObjectAllocator(uint32_t type, size_t block_size);
+ void* alloc();
+ void free(void* ptr);
+
+ size_t get_block_size() const { return block_size_; }
+ private:
+ void alloc_page();
+ void free_page(linker_vector_t::iterator page_record);
+ linker_vector_t::iterator find_page_record(void* ptr);
+ void create_page_record(void* page_addr, size_t free_blocks_cnt);
+
+ uint32_t type_;
+ size_t block_size_;
+
+ size_t free_pages_cnt_;
+ small_object_block_record* free_blocks_list_;
+
+ // sorted vector of page records
+ linker_vector_t page_records_;
+};
+
+class LinkerMemoryAllocator {
+ public:
+ constexpr LinkerMemoryAllocator() : allocators_(nullptr), allocators_buf_() {}
+ void* alloc(size_t size);
+
+ // Note that this implementation of realloc never shrinks allocation
+ void* realloc(void* ptr, size_t size);
+ void free(void* ptr);
+ private:
+ void* alloc_mmap(size_t size);
+ page_info* get_page_info(void* ptr);
+ LinkerSmallObjectAllocator* get_small_object_allocator(uint32_t type);
+ void initialize_allocators();
+
+ LinkerSmallObjectAllocator* allocators_;
+ uint8_t allocators_buf_[sizeof(LinkerSmallObjectAllocator)*kSmallObjectAllocatorsCount];
+};
+
+
+#endif /* __LINKER_ALLOCATOR_H */
diff --git a/linker/linker_block_allocator.cpp b/linker/linker_block_allocator.cpp
new file mode 100644
index 0000000..23298a4
--- /dev/null
+++ b/linker/linker_block_allocator.cpp
@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker_block_allocator.h"
+#include <inttypes.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include "private/bionic_prctl.h"
+
+// the multiplier should be power of 2
+static constexpr size_t round_up(size_t size, size_t multiplier) {
+ return (size + (multiplier - 1)) & ~(multiplier-1);
+}
+
+struct LinkerBlockAllocatorPage {
+ LinkerBlockAllocatorPage* next;
+ uint8_t bytes[PAGE_SIZE - 16] __attribute__((aligned(16)));
+};
+
+struct FreeBlockInfo {
+ void* next_block;
+ size_t num_free_blocks;
+};
+
+LinkerBlockAllocator::LinkerBlockAllocator(size_t block_size)
+ : block_size_(
+ round_up(block_size < sizeof(FreeBlockInfo) ? sizeof(FreeBlockInfo) : block_size, 16)),
+ page_list_(nullptr),
+ free_block_list_(nullptr)
+{}
+
+void* LinkerBlockAllocator::alloc() {
+ if (free_block_list_ == nullptr) {
+ create_new_page();
+ }
+
+ FreeBlockInfo* block_info = reinterpret_cast<FreeBlockInfo*>(free_block_list_);
+ if (block_info->num_free_blocks > 1) {
+ FreeBlockInfo* next_block_info = reinterpret_cast<FreeBlockInfo*>(
+ reinterpret_cast<char*>(free_block_list_) + block_size_);
+ next_block_info->next_block = block_info->next_block;
+ next_block_info->num_free_blocks = block_info->num_free_blocks - 1;
+ free_block_list_ = next_block_info;
+ } else {
+ free_block_list_ = block_info->next_block;
+ }
+
+ memset(block_info, 0, block_size_);
+
+ return block_info;
+}
+
+void LinkerBlockAllocator::free(void* block) {
+ if (block == nullptr) {
+ return;
+ }
+
+ LinkerBlockAllocatorPage* page = find_page(block);
+
+ if (page == nullptr) {
+ abort();
+ }
+
+ ssize_t offset = reinterpret_cast<uint8_t*>(block) - page->bytes;
+
+ if (offset % block_size_ != 0) {
+ abort();
+ }
+
+ memset(block, 0, block_size_);
+
+ FreeBlockInfo* block_info = reinterpret_cast<FreeBlockInfo*>(block);
+
+ block_info->next_block = free_block_list_;
+ block_info->num_free_blocks = 1;
+
+ free_block_list_ = block_info;
+}
+
+void LinkerBlockAllocator::protect_all(int prot) {
+ for (LinkerBlockAllocatorPage* page = page_list_; page != nullptr; page = page->next) {
+ if (mprotect(page, PAGE_SIZE, prot) == -1) {
+ abort();
+ }
+ }
+}
+
+void LinkerBlockAllocator::create_new_page() {
+ static_assert(sizeof(LinkerBlockAllocatorPage) == PAGE_SIZE,
+ "Invalid sizeof(LinkerBlockAllocatorPage)");
+
+ LinkerBlockAllocatorPage* page = reinterpret_cast<LinkerBlockAllocatorPage*>(
+ mmap(nullptr, PAGE_SIZE, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0));
+
+ if (page == MAP_FAILED) {
+ abort(); // oom
+ }
+
+ prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, page, PAGE_SIZE, "linker_alloc");
+
+ memset(page, 0, PAGE_SIZE);
+
+ FreeBlockInfo* first_block = reinterpret_cast<FreeBlockInfo*>(page->bytes);
+ first_block->next_block = free_block_list_;
+ first_block->num_free_blocks = (PAGE_SIZE - sizeof(LinkerBlockAllocatorPage*))/block_size_;
+
+ free_block_list_ = first_block;
+
+ page->next = page_list_;
+ page_list_ = page;
+}
+
+LinkerBlockAllocatorPage* LinkerBlockAllocator::find_page(void* block) {
+ if (block == nullptr) {
+ abort();
+ }
+
+ LinkerBlockAllocatorPage* page = page_list_;
+ while (page != nullptr) {
+ const uint8_t* page_ptr = reinterpret_cast<const uint8_t*>(page);
+ if (block >= (page_ptr + sizeof(page->next)) && block < (page_ptr + PAGE_SIZE)) {
+ return page;
+ }
+
+ page = page->next;
+ }
+
+ abort();
+}
diff --git a/linker/linker_block_allocator.h b/linker/linker_block_allocator.h
new file mode 100644
index 0000000..4b9b995
--- /dev/null
+++ b/linker/linker_block_allocator.h
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LINKER_BLOCK_ALLOCATOR_H
+#define __LINKER_BLOCK_ALLOCATOR_H
+
+#include <stdlib.h>
+#include <limits.h>
+#include "private/bionic_macros.h"
+
+struct LinkerBlockAllocatorPage;
+
+/*
+ * This class is a non-template version of the LinkerTypeAllocator
+ * It keeps code inside .cpp file by keeping the interface
+ * template-free.
+ *
+ * Please use LinkerTypeAllocator<type> where possible (everywhere).
+ */
+class LinkerBlockAllocator {
+ public:
+ explicit LinkerBlockAllocator(size_t block_size);
+
+ void* alloc();
+ void free(void* block);
+ void protect_all(int prot);
+
+ private:
+ void create_new_page();
+ LinkerBlockAllocatorPage* find_page(void* block);
+
+ size_t block_size_;
+ LinkerBlockAllocatorPage* page_list_;
+ void* free_block_list_;
+
+ DISALLOW_COPY_AND_ASSIGN(LinkerBlockAllocator);
+};
+
+/*
+ * A simple allocator for the dynamic linker. An allocator allocates instances
+ * of a single fixed-size type. Allocations are backed by page-sized private
+ * anonymous mmaps.
+ *
+ * The differences between this allocator and LinkerMemoryAllocator are:
+ * 1. This allocator manages space more efficiently. LinkerMemoryAllocator
+ * operates in power-of-two sized blocks up to 1k, when this implementation
+ * splits the page to aligned size of structure; For example for structures
+ * with size 513 this allocator will use 516 (520 for lp64) bytes of data
+ * where generalized implementation is going to use 1024 sized blocks.
+ *
+ * 2. This allocator does not munmap allocated memory, where LinkerMemoryAllocator does.
+ *
+ * 3. This allocator provides mprotect services to the user, where LinkerMemoryAllocator
+ * always treats it's memory as READ|WRITE.
+ */
+template<typename T>
+class LinkerTypeAllocator {
+ public:
+ LinkerTypeAllocator() : block_allocator_(sizeof(T)) {}
+ T* alloc() { return reinterpret_cast<T*>(block_allocator_.alloc()); }
+ void free(T* t) { block_allocator_.free(t); }
+ void protect_all(int prot) { block_allocator_.protect_all(prot); }
+ private:
+ LinkerBlockAllocator block_allocator_;
+ DISALLOW_COPY_AND_ASSIGN(LinkerTypeAllocator);
+};
+
+#endif // __LINKER_BLOCK_ALLOCATOR_H
diff --git a/linker/linker_common_types.h b/linker/linker_common_types.h
new file mode 100644
index 0000000..6afd950
--- /dev/null
+++ b/linker/linker_common_types.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef __LINKER_COMMON_TYPES_H
+#define __LINKER_COMMON_TYPES_H
+
+#include <android/dlext.h>
+#include "linked_list.h"
+
+// TODO(dimitry): move this to linker_defines.h? Unless it is removed by
+// consequent refactoring steps.
+
+// Android uses RELA for aarch64 and x86_64. mips64 still uses REL.
+#if defined(__aarch64__) || defined(__x86_64__)
+#define USE_RELA 1
+#endif
+
+
+struct soinfo;
+
+class SoinfoListAllocator {
+ public:
+ static LinkedListEntry<soinfo>* alloc();
+ static void free(LinkedListEntry<soinfo>* entry);
+
+ private:
+ // unconstructable
+ DISALLOW_IMPLICIT_CONSTRUCTORS(SoinfoListAllocator);
+};
+
+class NamespaceListAllocator {
+ public:
+ static LinkedListEntry<android_namespace_t>* alloc();
+ static void free(LinkedListEntry<android_namespace_t>* entry);
+
+ private:
+ // unconstructable
+ DISALLOW_IMPLICIT_CONSTRUCTORS(NamespaceListAllocator);
+};
+
+typedef LinkedList<soinfo, SoinfoListAllocator> soinfo_list_t;
+typedef LinkedList<android_namespace_t, NamespaceListAllocator> android_namespace_list_t;
+
+#endif /* __LINKER_COMMON_TYPES_H */
diff --git a/linker/linker_debug.h b/linker/linker_debug.h
new file mode 100644
index 0000000..5af9929
--- /dev/null
+++ b/linker/linker_debug.h
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _LINKER_DEBUG_H_
+#define _LINKER_DEBUG_H_
+
+// You can increase the verbosity of debug traces by defining the LD_DEBUG
+// environment variable to a numeric value from 0 to 2 (corresponding to
+// INFO, TRACE, and DEBUG calls in the source). This will only
+// affect new processes being launched.
+
+// By default, traces are sent to logcat, with the "linker" tag. You can
+// change this to go to stdout instead by setting the definition of
+// LINKER_DEBUG_TO_LOG to 0.
+#define LINKER_DEBUG_TO_LOG 1
+
+#define TRACE_DEBUG 1
+#define DO_TRACE_LOOKUP 1
+#define DO_TRACE_RELO 1
+#define DO_TRACE_IFUNC 1
+#define TIMING 0
+#define STATS 0
+#define COUNT_PAGES 0
+
+/*********************************************************************
+ * You shouldn't need to modify anything below unless you are adding
+ * more debugging information.
+ *
+ * To enable/disable specific debug options, change the defines above
+ *********************************************************************/
+
+#include "private/libc_logging.h"
+#include <unistd.h>
+
+__LIBC_HIDDEN__ extern int g_ld_debug_verbosity;
+
+#define CHECK(predicate) { \
+ if (!(predicate)) { \
+ __libc_fatal("%s:%d: %s CHECK '" #predicate "' failed", \
+ __FILE__, __LINE__, __FUNCTION__); \
+ } \
+ }
+
+#if LINKER_DEBUG_TO_LOG
+#define _PRINTVF(v, x...) \
+ do { \
+ if (g_ld_debug_verbosity > (v)) __libc_format_log(5-(v), "linker", x); \
+ } while (0)
+#else /* !LINKER_DEBUG_TO_LOG */
+#define _PRINTVF(v, x...) \
+ do { \
+ if (g_ld_debug_verbosity > (v)) { __libc_format_fd(1, x); write(1, "\n", 1); } \
+ } while (0)
+#endif /* !LINKER_DEBUG_TO_LOG */
+
+#define PRINT(x...) _PRINTVF(-1, x)
+#define INFO(x...) _PRINTVF(0, x)
+#define TRACE(x...) _PRINTVF(1, x)
+
+#if TRACE_DEBUG
+#define DEBUG(x...) _PRINTVF(2, "DEBUG: " x)
+#else /* !TRACE_DEBUG */
+#define DEBUG(x...) do {} while (0)
+#endif /* TRACE_DEBUG */
+
+#define TRACE_TYPE(t, x...) do { if (DO_TRACE_##t) { TRACE(x); } } while (0)
+
+#if COUNT_PAGES
+extern uint32_t bitmask[];
+#if defined(__LP64__)
+#define MARK(offset) \
+ do { \
+ if ((((offset) >> 12) >> 5) < 4096) \
+ bitmask[((offset) >> 12) >> 5] |= (1 << (((offset) >> 12) & 31)); \
+ } while (0)
+#else
+#define MARK(offset) \
+ do { \
+ bitmask[((offset) >> 12) >> 3] |= (1 << (((offset) >> 12) & 7)); \
+ } while (0)
+#endif
+#else
+#define MARK(x) do {} while (0)
+
+#endif
+
+#endif /* _LINKER_DEBUG_H_ */
diff --git a/linker/linker_dlwarning.cpp b/linker/linker_dlwarning.cpp
new file mode 100644
index 0000000..c53ad66
--- /dev/null
+++ b/linker/linker_dlwarning.cpp
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker_dlwarning.h"
+
+#include <strings.h>
+
+#include <string>
+
+static std::string current_msg;
+
+void add_dlwarning(const char* sopath, const char* message, const char* value) {
+ if (!current_msg.empty()) {
+ current_msg += '\n';
+ }
+
+ current_msg = current_msg + basename(sopath) + ": " + message;
+
+ if (value != nullptr) {
+ current_msg = current_msg + " \"" + value + "\"";
+ }
+}
+
+// Resets the current one (like dlerror but instead of
+// being thread-local it is process-local).
+void get_dlwarning(void* obj, void (*f)(void*, const char*)) {
+ if (current_msg.empty()) {
+ f(obj, nullptr);
+ } else {
+ std::string msg = current_msg;
+ current_msg.clear();
+ f(obj, msg.c_str());
+ }
+}
diff --git a/linker/linker_dlwarning.h b/linker/linker_dlwarning.h
new file mode 100644
index 0000000..0263c72
--- /dev/null
+++ b/linker/linker_dlwarning.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LINKER_DLWARNING_H
+#define __LINKER_DLWARNING_H
+
+void add_dlwarning(const char* sopath, const char* message, const char* value = nullptr);
+
+// Resets the current one (like dlerror but instead of
+// being thread-local it is process-local). The user_data
+// is used to avoid forcing user into saving the message
+// to a global variable.
+void get_dlwarning(void* user_data, void (*f)(void*, const char*));
+
+#endif /* __LINKER_DLWARNING_H */
diff --git a/linker/linker_gdb_support.cpp b/linker/linker_gdb_support.cpp
new file mode 100644
index 0000000..de74087
--- /dev/null
+++ b/linker/linker_gdb_support.cpp
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker_gdb_support.h"
+
+#include <pthread.h>
+
+#include "private/ScopedPthreadMutexLocker.h"
+
+// This function is an empty stub where GDB locates a breakpoint to get notified
+// about linker activity.
+extern "C"
+void __attribute__((noinline)) __attribute__((visibility("default"))) rtld_db_dlactivity();
+
+r_debug _r_debug =
+ {1, nullptr, reinterpret_cast<uintptr_t>(&rtld_db_dlactivity), r_debug::RT_CONSISTENT, 0};
+
+static pthread_mutex_t g__r_debug_mutex = PTHREAD_MUTEX_INITIALIZER;
+static link_map* r_debug_tail = nullptr;
+
+void insert_link_map_into_debug_map(link_map* map) {
+ // Stick the new library at the end of the list.
+ // gdb tends to care more about libc than it does
+ // about leaf libraries, and ordering it this way
+ // reduces the back-and-forth over the wire.
+ if (r_debug_tail != nullptr) {
+ r_debug_tail->l_next = map;
+ map->l_prev = r_debug_tail;
+ map->l_next = nullptr;
+ } else {
+ _r_debug.r_map = map;
+ map->l_prev = nullptr;
+ map->l_next = nullptr;
+ }
+ r_debug_tail = map;
+}
+
+void remove_link_map_from_debug_map(link_map* map) {
+ if (r_debug_tail == map) {
+ r_debug_tail = map->l_prev;
+ }
+
+ if (map->l_prev) {
+ map->l_prev->l_next = map->l_next;
+ }
+ if (map->l_next) {
+ map->l_next->l_prev = map->l_prev;
+ }
+}
+
+void notify_gdb_of_load(link_map* map) {
+ ScopedPthreadMutexLocker locker(&g__r_debug_mutex);
+
+ _r_debug.r_state = r_debug::RT_ADD;
+ rtld_db_dlactivity();
+
+ insert_link_map_into_debug_map(map);
+
+ _r_debug.r_state = r_debug::RT_CONSISTENT;
+ rtld_db_dlactivity();
+}
+
+void notify_gdb_of_unload(link_map* map) {
+ ScopedPthreadMutexLocker locker(&g__r_debug_mutex);
+
+ _r_debug.r_state = r_debug::RT_DELETE;
+ rtld_db_dlactivity();
+
+ remove_link_map_from_debug_map(map);
+
+ _r_debug.r_state = r_debug::RT_CONSISTENT;
+ rtld_db_dlactivity();
+}
+
+void notify_gdb_of_libraries() {
+ _r_debug.r_state = r_debug::RT_ADD;
+ rtld_db_dlactivity();
+ _r_debug.r_state = r_debug::RT_CONSISTENT;
+ rtld_db_dlactivity();
+}
+
diff --git a/linker/linker_gdb_support.h b/linker/linker_gdb_support.h
new file mode 100644
index 0000000..2a590ba
--- /dev/null
+++ b/linker/linker_gdb_support.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef __LINKER_GDB_SUPPORT_H
+#define __LINKER_GDB_SUPPORT_H
+
+#include <link.h>
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+void insert_link_map_into_debug_map(link_map* map);
+void remove_link_map_from_debug_map(link_map* map);
+void notify_gdb_of_load(link_map* map);
+void notify_gdb_of_unload(link_map* map);
+void notify_gdb_of_libraries();
+
+extern struct r_debug _r_debug;
+
+__END_DECLS
+
+#endif
diff --git a/linker/linker_globals.cpp b/linker/linker_globals.cpp
new file mode 100644
index 0000000..155ebf4
--- /dev/null
+++ b/linker/linker_globals.cpp
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+
+#include "linker_globals.h"
+#include "linker_namespaces.h"
+
+int g_argc = 0;
+char** g_argv = nullptr;
+char** g_envp = nullptr;
+
+android_namespace_t g_default_namespace;
+
+std::unordered_map<uintptr_t, soinfo*> g_soinfo_handles_map;
+
+static char __linker_dl_err_buf[768];
+
+char* linker_get_error_buffer() {
+ return &__linker_dl_err_buf[0];
+}
+
+size_t linker_get_error_buffer_size() {
+ return sizeof(__linker_dl_err_buf);
+}
+
diff --git a/linker/linker_globals.h b/linker/linker_globals.h
new file mode 100644
index 0000000..b6f8a04
--- /dev/null
+++ b/linker/linker_globals.h
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef __LINKER_GLOBALS_H
+#define __LINKER_GLOBALS_H
+
+#include <link.h>
+#include <stddef.h>
+
+#include <unordered_map>
+
+#define DL_ERR(fmt, x...) \
+ do { \
+ __libc_format_buffer(linker_get_error_buffer(), linker_get_error_buffer_size(), fmt, ##x); \
+ /* If LD_DEBUG is set high enough, log every dlerror(3) message. */ \
+ LD_LOG(kLogErrors, "%s\n", linker_get_error_buffer()); \
+ } while (false)
+
+#define DL_WARN(fmt, x...) \
+ do { \
+ __libc_format_log(ANDROID_LOG_WARN, "linker", fmt, ##x); \
+ __libc_format_fd(2, "WARNING: linker: "); \
+ __libc_format_fd(2, fmt, ##x); \
+ __libc_format_fd(2, "\n"); \
+ } while (false)
+
+#define DL_ERR_AND_LOG(fmt, x...) \
+ do { \
+ DL_ERR(fmt, x); \
+ PRINT(fmt, x); \
+ } while (false)
+
+constexpr ElfW(Versym) kVersymNotNeeded = 0;
+constexpr ElfW(Versym) kVersymGlobal = 1;
+
+// These values are used to call constructors for .init_array && .preinit_array
+extern int g_argc;
+extern char** g_argv;
+extern char** g_envp;
+
+struct soinfo;
+struct android_namespace_t;
+
+extern android_namespace_t g_default_namespace;
+
+extern std::unordered_map<uintptr_t, soinfo*> g_soinfo_handles_map;
+
+// Error buffer "variable"
+char* linker_get_error_buffer();
+size_t linker_get_error_buffer_size();
+
+#endif /* __LINKER_GLOBALS_H */
diff --git a/linker/linker_libc_support.c b/linker/linker_libc_support.c
new file mode 100644
index 0000000..77a0252
--- /dev/null
+++ b/linker/linker_libc_support.c
@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "../libc/arch-common/bionic/__dso_handle.h"
+#include "../libc/arch-common/bionic/pthread_atfork.h"
+
+int atexit(void (*function)(void) __attribute__((__unused__))) {
+ return -1;
+}
+
diff --git a/linker/linker_logger.cpp b/linker/linker_logger.cpp
new file mode 100644
index 0000000..a9d358a
--- /dev/null
+++ b/linker/linker_logger.cpp
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <string.h>
+#include <sys/prctl.h>
+#include <sys/system_properties.h>
+#include <unistd.h>
+
+#include <string>
+#include <vector>
+
+#include "android-base/strings.h"
+#include "linker_logger.h"
+#include "private/libc_logging.h"
+
+LinkerLogger g_linker_logger;
+
+static const char* kSystemLdDebugProperty = "debug.ld.all";
+static const char* kLdDebugPropertyPrefix = "debug.ld.app.";
+
+static const char* kOptionErrors = "dlerror";
+static const char* kOptionDlopen = "dlopen";
+
+static std::string property_get(const char* name) {
+ char value[PROP_VALUE_MAX] = {};
+ __system_property_get(name, value);
+ return value;
+}
+
+static uint32_t ParseProperty(const std::string& value) {
+ if (value.empty()) {
+ return 0;
+ }
+
+ std::vector<std::string> options = android::base::Split(value, ",");
+
+ uint32_t flags = 0;
+
+ for (const auto& o : options) {
+ if (o == kOptionErrors) {
+ flags |= kLogErrors;
+ } else if (o == kOptionDlopen){
+ flags |= kLogDlopen;
+ } else {
+ __libc_format_log(ANDROID_LOG_WARN, "linker", "Unknown debug.ld option \"%s\", will ignore.", o.c_str());
+ }
+ }
+
+ return flags;
+}
+
+void LinkerLogger::ResetState() {
+ // the most likely scenario app is not debuggable and
+ // is running on user build - the logging is disabled.
+ if (prctl(PR_GET_DUMPABLE, 0, 0, 0, 0) == 0) {
+ return;
+ }
+
+ flags_ = 0;
+ // check flag applied to all processes first
+ std::string value = property_get(kSystemLdDebugProperty);
+ flags_ |= ParseProperty(value);
+
+ // get process basename
+ std::string process_name = basename(g_argv[0]);
+
+ std::string property_name = std::string(kLdDebugPropertyPrefix) + process_name;
+
+ // Property names are limited to PROP_NAME_MAX.
+
+ if (property_name.size() >= PROP_NAME_MAX) {
+ size_t count = PROP_NAME_MAX - 1;
+ // remove trailing dots...
+ while (property_name[count-1] == '.') {
+ --count;
+ }
+
+ property_name = property_name.substr(0, count);
+ }
+ value = property_get(property_name.c_str());
+ flags_ |= ParseProperty(value);
+}
+
+void LinkerLogger::Log(uint32_t type, const char* format, ...) {
+ if ((flags_ & type) == 0) {
+ return;
+ }
+
+ va_list ap;
+ va_start(ap, format);
+ __libc_format_log_va_list(ANDROID_LOG_DEBUG, "linker", format, ap);
+ va_end(ap);
+}
+
diff --git a/linker/linker_logger.h b/linker/linker_logger.h
new file mode 100644
index 0000000..0932471
--- /dev/null
+++ b/linker/linker_logger.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _LINKER_LOGGER_H_
+#define _LINKER_LOGGER_H_
+
+#include <stdlib.h>
+#include <limits.h>
+#include "private/bionic_macros.h"
+
+#define LD_LOG(type, x...) \
+ { \
+ g_linker_logger.Log(type, x); \
+ }
+
+constexpr const uint32_t kLogErrors = 1 << 0;
+constexpr const uint32_t kLogDlopen = 1 << 1;
+
+class LinkerLogger {
+ public:
+ LinkerLogger() : flags_(0) { }
+
+ void ResetState();
+ void Log(uint32_t type, const char* format, ...);
+ private:
+ uint32_t flags_;
+
+ DISALLOW_COPY_AND_ASSIGN(LinkerLogger);
+};
+
+extern LinkerLogger g_linker_logger;
+extern char** g_argv;
+
+#endif /* _LINKER_LOGGER_H_ */
diff --git a/linker/linker_mapped_file_fragment.cpp b/linker/linker_mapped_file_fragment.cpp
new file mode 100644
index 0000000..27c1c69
--- /dev/null
+++ b/linker/linker_mapped_file_fragment.cpp
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker_mapped_file_fragment.h"
+#include "linker_debug.h"
+#include "linker_utils.h"
+
+#include <inttypes.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+MappedFileFragment::MappedFileFragment() : map_start_(nullptr), map_size_(0),
+ data_(nullptr), size_ (0)
+{ }
+
+MappedFileFragment::~MappedFileFragment() {
+ if (map_start_ != nullptr) {
+ munmap(map_start_, map_size_);
+ }
+}
+
+bool MappedFileFragment::Map(int fd, off64_t base_offset, size_t elf_offset, size_t size) {
+ off64_t offset;
+ CHECK(safe_add(&offset, base_offset, elf_offset));
+
+ off64_t page_min = page_start(offset);
+ off64_t end_offset;
+
+ CHECK(safe_add(&end_offset, offset, size));
+ CHECK(safe_add(&end_offset, end_offset, page_offset(offset)));
+
+ size_t map_size = static_cast<size_t>(end_offset - page_min);
+ CHECK(map_size >= size);
+
+ uint8_t* map_start = static_cast<uint8_t*>(
+ mmap64(nullptr, map_size, PROT_READ, MAP_PRIVATE, fd, page_min));
+
+ if (map_start == MAP_FAILED) {
+ return false;
+ }
+
+ map_start_ = map_start;
+ map_size_ = map_size;
+
+ data_ = map_start + page_offset(offset);
+ size_ = size;
+
+ return true;
+}
diff --git a/linker/linker_mapped_file_fragment.h b/linker/linker_mapped_file_fragment.h
new file mode 100644
index 0000000..91bd077
--- /dev/null
+++ b/linker/linker_mapped_file_fragment.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef LINKER_MAPPED_FILE_FRAGMENT_H
+#define LINKER_MAPPED_FILE_FRAGMENT_H
+
+#include <unistd.h>
+
+#include "private/bionic_macros.h"
+
+class MappedFileFragment {
+ public:
+ MappedFileFragment();
+ ~MappedFileFragment();
+
+ bool Map(int fd, off64_t base_offset, size_t elf_offset, size_t size);
+
+ void* data() const { return data_; }
+ size_t size() const { return size_; }
+ private:
+ void* map_start_;
+ size_t map_size_;
+ void* data_;
+ size_t size_;
+
+ DISALLOW_COPY_AND_ASSIGN(MappedFileFragment);
+};
+
+#endif /* LINKER_MAPPED_FILE_FRAGMENT_H */
diff --git a/linker/linker_memory.cpp b/linker/linker_memory.cpp
new file mode 100644
index 0000000..1892d02
--- /dev/null
+++ b/linker/linker_memory.cpp
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker_allocator.h"
+
+#include <stdlib.h>
+
+static LinkerMemoryAllocator g_linker_allocator;
+
+void* malloc(size_t byte_count) {
+ return g_linker_allocator.alloc(byte_count);
+}
+
+void* calloc(size_t item_count, size_t item_size) {
+ return g_linker_allocator.alloc(item_count*item_size);
+}
+
+void* realloc(void* p, size_t byte_count) {
+ return g_linker_allocator.realloc(p, byte_count);
+}
+
+void free(void* ptr) {
+ g_linker_allocator.free(ptr);
+}
+
diff --git a/linker/linker_mips.cpp b/linker/linker_mips.cpp
new file mode 100644
index 0000000..cd392dc
--- /dev/null
+++ b/linker/linker_mips.cpp
@@ -0,0 +1,333 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if !defined(__LP64__) && __mips_isa_rev >= 5
+#include <sys/prctl.h>
+#endif
+
+#include "linker.h"
+#include "linker_debug.h"
+#include "linker_globals.h"
+#include "linker_phdr.h"
+#include "linker_relocs.h"
+#include "linker_reloc_iterators.h"
+#include "linker_sleb128.h"
+#include "linker_soinfo.h"
+
+template bool soinfo::relocate<plain_reloc_iterator>(const VersionTracker& version_tracker,
+ plain_reloc_iterator&& rel_iterator,
+ const soinfo_list_t& global_group,
+ const soinfo_list_t& local_group);
+
+template bool soinfo::relocate<packed_reloc_iterator<sleb128_decoder>>(
+ const VersionTracker& version_tracker,
+ packed_reloc_iterator<sleb128_decoder>&& rel_iterator,
+ const soinfo_list_t& global_group,
+ const soinfo_list_t& local_group);
+
+template <typename ElfRelIteratorT>
+bool soinfo::relocate(const VersionTracker& version_tracker,
+ ElfRelIteratorT&& rel_iterator,
+ const soinfo_list_t& global_group,
+ const soinfo_list_t& local_group) {
+ for (size_t idx = 0; rel_iterator.has_next(); ++idx) {
+ const auto rel = rel_iterator.next();
+
+ if (rel == nullptr) {
+ return false;
+ }
+
+ ElfW(Word) type = ELFW(R_TYPE)(rel->r_info);
+ ElfW(Word) sym = ELFW(R_SYM)(rel->r_info);
+
+ ElfW(Addr) reloc = static_cast<ElfW(Addr)>(rel->r_offset + load_bias);
+ ElfW(Addr) sym_addr = 0;
+ const char* sym_name = nullptr;
+
+ DEBUG("Processing \"%s\" relocation at index %zd", get_realpath(), idx);
+ if (type == R_GENERIC_NONE) {
+ continue;
+ }
+
+ const ElfW(Sym)* s = nullptr;
+ soinfo* lsi = nullptr;
+
+ if (sym != 0) {
+ sym_name = get_string(symtab_[sym].st_name);
+ const version_info* vi = nullptr;
+
+ if (!lookup_version_info(version_tracker, sym, sym_name, &vi)) {
+ return false;
+ }
+
+ if (!soinfo_do_lookup(this, sym_name, vi, &lsi, global_group, local_group, &s)) {
+ return false;
+ }
+
+ if (s == nullptr) {
+ // mips does not support relocation with weak-undefined symbols
+ DL_ERR("cannot locate symbol \"%s\" referenced by \"%s\"...",
+ sym_name, get_realpath());
+ return false;
+ } else {
+ // We got a definition.
+ sym_addr = lsi->resolve_symbol_address(s);
+ }
+ count_relocation(kRelocSymbol);
+ }
+
+ switch (type) {
+ case R_MIPS_REL32:
+#if defined(__LP64__)
+ // MIPS Elf64_Rel entries contain compound relocations
+ // We only handle the R_MIPS_NONE|R_MIPS_64|R_MIPS_REL32 case
+ if (ELF64_R_TYPE2(rel->r_info) != R_MIPS_64 ||
+ ELF64_R_TYPE3(rel->r_info) != R_MIPS_NONE) {
+ DL_ERR("Unexpected compound relocation type:%d type2:%d type3:%d @ %p (%zu)",
+ type, static_cast<unsigned>(ELF64_R_TYPE2(rel->r_info)),
+ static_cast<unsigned>(ELF64_R_TYPE3(rel->r_info)), rel, idx);
+ return false;
+ }
+#endif
+ count_relocation(s == nullptr ? kRelocAbsolute : kRelocRelative);
+ MARK(rel->r_offset);
+ TRACE_TYPE(RELO, "RELO REL32 %08zx <- %08zx %s", static_cast<size_t>(reloc),
+ static_cast<size_t>(sym_addr), sym_name ? sym_name : "*SECTIONHDR*");
+ if (s != nullptr) {
+ *reinterpret_cast<ElfW(Addr)*>(reloc) += sym_addr;
+ } else {
+ *reinterpret_cast<ElfW(Addr)*>(reloc) += load_bias;
+ }
+ break;
+ default:
+ DL_ERR("unknown reloc type %d @ %p (%zu)", type, rel, idx);
+ return false;
+ }
+ }
+ return true;
+}
+
+bool soinfo::mips_relocate_got(const VersionTracker& version_tracker,
+ const soinfo_list_t& global_group,
+ const soinfo_list_t& local_group) {
+ ElfW(Addr)** got = plt_got_;
+ if (got == nullptr) {
+ return true;
+ }
+
+ // got[0] is the address of the lazy resolver function.
+ // got[1] may be used for a GNU extension.
+ // Set it to a recognizable address in case someone calls it (should be _rtld_bind_start).
+ // FIXME: maybe this should be in a separate routine?
+ if ((flags_ & FLAG_LINKER) == 0) {
+ size_t g = 0;
+ got[g++] = reinterpret_cast<ElfW(Addr)*>(0xdeadbeef);
+ if (reinterpret_cast<intptr_t>(got[g]) < 0) {
+ got[g++] = reinterpret_cast<ElfW(Addr)*>(0xdeadfeed);
+ }
+ // Relocate the local GOT entries.
+ for (; g < mips_local_gotno_; g++) {
+ got[g] = reinterpret_cast<ElfW(Addr)*>(reinterpret_cast<uintptr_t>(got[g]) + load_bias);
+ }
+ }
+
+ // Now for the global GOT entries...
+ got = plt_got_ + mips_local_gotno_;
+ for (ElfW(Word) sym = mips_gotsym_; sym < mips_symtabno_; sym++, got++) {
+ // This is an undefined reference... try to locate it.
+ const ElfW(Sym)* local_sym = symtab_ + sym;
+ const char* sym_name = get_string(local_sym->st_name);
+ soinfo* lsi = nullptr;
+ const ElfW(Sym)* s = nullptr;
+
+ ElfW(Word) st_visibility = (local_sym->st_other & 0x3);
+
+ if (st_visibility == STV_DEFAULT) {
+ const version_info* vi = nullptr;
+
+ if (!lookup_version_info(version_tracker, sym, sym_name, &vi)) {
+ return false;
+ }
+
+ if (!soinfo_do_lookup(this, sym_name, vi, &lsi, global_group, local_group, &s)) {
+ return false;
+ }
+ } else if (st_visibility == STV_PROTECTED) {
+ if (local_sym->st_value == 0) {
+ DL_ERR("%s: invalid symbol \"%s\" (PROTECTED/UNDEFINED) ",
+ get_realpath(), sym_name);
+ return false;
+ }
+ s = local_sym;
+ lsi = this;
+ } else {
+ DL_ERR("%s: invalid symbol \"%s\" visibility: 0x%x",
+ get_realpath(), sym_name, st_visibility);
+ return false;
+ }
+
+ if (s == nullptr) {
+ // We only allow an undefined symbol if this is a weak reference.
+ if (ELF_ST_BIND(local_sym->st_info) != STB_WEAK) {
+ DL_ERR("%s: cannot locate \"%s\"...", get_realpath(), sym_name);
+ return false;
+ }
+ *got = 0;
+ } else {
+ // FIXME: is this sufficient?
+ // For reference see NetBSD link loader
+ // http://cvsweb.netbsd.org/bsdweb.cgi/src/libexec/ld.elf_so/arch/mips/mips_reloc.c?rev=1.53&content-type=text/x-cvsweb-markup
+ *got = reinterpret_cast<ElfW(Addr)*>(lsi->resolve_symbol_address(s));
+ }
+ }
+ return true;
+}
+
+#if !defined(__LP64__)
+
+// Checks for mips32's various floating point abis.
+// (Mips64 Android has a single floating point abi and doesn't need any checks)
+
+// Linux kernel has declarations similar to the following
+// in <linux>/arch/mips/include/asm/elf.h,
+// but that non-uapi internal header file will never be imported
+// into bionic's kernel headers.
+
+#define PT_MIPS_ABIFLAGS 0x70000003 // is .MIPS.abiflags segment
+
+struct mips_elf_abiflags_v0 {
+ uint16_t version; // version of this structure
+ uint8_t isa_level, isa_rev, gpr_size, cpr1_size, cpr2_size;
+ uint8_t fp_abi; // mips32 ABI variants for floating point
+ uint32_t isa_ext, ases, flags1, flags2;
+};
+
+// Bits of flags1:
+#define MIPS_AFL_FLAGS1_ODDSPREG 1 // Uses odd-numbered single-prec fp regs
+
+// Some values of fp_abi: via compiler flag:
+#define MIPS_ABI_FP_DOUBLE 1 // -mdouble-float
+#define MIPS_ABI_FP_XX 5 // -mfpxx
+#define MIPS_ABI_FP_64A 7 // -mips32r* -mfp64 -mno-odd-spreg
+
+#if __mips_isa_rev >= 5
+static bool mips_fre_mode_on = false; // have set FRE=1 mode for process
+#endif
+
+bool soinfo::mips_check_and_adjust_fp_modes() {
+ mips_elf_abiflags_v0* abiflags = nullptr;
+ int mips_fpabi;
+
+ // Find soinfo's optional .MIPS.abiflags segment
+ for (size_t i = 0; i<phnum; ++i) {
+ const ElfW(Phdr)& ph = phdr[i];
+ if (ph.p_type == PT_MIPS_ABIFLAGS) {
+ if (ph.p_filesz < sizeof (mips_elf_abiflags_v0)) {
+ DL_ERR("Corrupt PT_MIPS_ABIFLAGS header found \"%s\"", get_realpath());
+ return false;
+ }
+ abiflags = reinterpret_cast<mips_elf_abiflags_v0*>(ph.p_vaddr + load_bias);
+ break;
+ }
+ }
+
+ // FP ABI-variant compatibility checks for MIPS o32 ABI
+ if (abiflags == nullptr) {
+ // Old compilers lack the new abiflags section.
+ // These compilers used -mfp32 -mdouble-float -modd-spreg defaults,
+ // ie FP32 aka DOUBLE, using odd-numbered single-prec regs
+ mips_fpabi = MIPS_ABI_FP_DOUBLE;
+ } else {
+ mips_fpabi = abiflags->fp_abi;
+ if ( (abiflags->flags1 & MIPS_AFL_FLAGS1_ODDSPREG)
+ && (mips_fpabi == MIPS_ABI_FP_XX ||
+ mips_fpabi == MIPS_ABI_FP_64A ) ) {
+ // Android supports fewer cases than Linux
+ DL_ERR("Unsupported odd-single-prec FloatPt reg uses in \"%s\"",
+ get_realpath());
+ return false;
+ }
+ }
+ if (!(mips_fpabi == MIPS_ABI_FP_DOUBLE ||
+#if __mips_isa_rev >= 5
+ mips_fpabi == MIPS_ABI_FP_64A ||
+#endif
+ mips_fpabi == MIPS_ABI_FP_XX )) {
+ DL_ERR("Unsupported MIPS32 FloatPt ABI %d found in \"%s\"",
+ mips_fpabi, get_realpath());
+ return false;
+ }
+
+#if __mips_isa_rev >= 5
+ // Adjust process's FR Emulation mode, if needed
+ //
+ // On Mips R5 & R6, Android runs continuously in FR=1 64bit-fpreg mode.
+ // NDK mips32 apps compiled with old compilers generate FP32 code
+ // which expects FR=0 32-bit fp registers.
+ // NDK mips32 apps compiled with newer compilers generate modeless
+ // FPXX code which runs on both FR=0 and FR=1 modes.
+ // Android itself is compiled in FP64A which requires FR=1 mode.
+ // FP32, FPXX, and FP64A all interlink okay, without dynamic FR mode
+ // changes during calls. For details, see
+ // http://dmz-portal.mips.com/wiki/MIPS_O32_ABI_-_FR0_and_FR1_Interlinking
+ // Processes containing FR32 FR=0 code are run via kernel software assist,
+ // which maps all odd-numbered single-precision reg refs onto the
+ // upper half of the paired even-numbered double-precision reg.
+ // FRE=1 triggers traps to the kernel's emulator on every single-precision
+ // fp op (for both odd and even-numbered registers).
+ // Turning on FRE=1 traps is done at most once per process, simultanously
+ // for all threads of that process, when dlopen discovers FP32 code.
+ // The kernel repacks threads' registers when FRE mode is turn on or off.
+ // These asynchronous adjustments are wrong if any thread was executing
+ // FPXX code using odd-numbered single-precision regs.
+ // Current Android compilers default to the -mno-oddspreg option,
+ // and this requirement is checked by Android's dlopen.
+ // So FRE can always be safely turned on for FP32, anytime.
+ // Deferred enhancement: Allow loading of odd-spreg FPXX modules.
+
+ if (mips_fpabi == MIPS_ABI_FP_DOUBLE && !mips_fre_mode_on) {
+ // Turn on FRE mode, which emulates mode-sensitive FR=0 code on FR=1
+ // register files, by trapping to kernel on refs to single-precision regs
+ if (prctl(PR_SET_FP_MODE, PR_FP_MODE_FR|PR_FP_MODE_FRE)) {
+ DL_ERR("Kernel or cpu failed to set FRE mode required for running \"%s\"",
+ get_realpath());
+ return false;
+ }
+ DL_WARN("Using FRE=1 mode to run \"%s\"", get_realpath());
+ mips_fre_mode_on = true; // Avoid future redundant mode-switch calls
+ // FRE mode is never turned back off.
+ // Deferred enhancement:
+ // Reset FRE mode when dlclose() removes all FP32 modules
+ }
+#else
+ // Android runs continuously in FR=0 32bit-fpreg mode.
+#endif // __mips_isa_rev
+ return true;
+}
+
+#endif // __LP64___
diff --git a/linker/linker_namespaces.cpp b/linker/linker_namespaces.cpp
new file mode 100644
index 0000000..675f324
--- /dev/null
+++ b/linker/linker_namespaces.cpp
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "linker_namespaces.h"
+#include "linker_utils.h"
+
+#include <vector>
+
+bool android_namespace_t::is_accessible(const std::string& file) {
+ if (!is_isolated_) {
+ return true;
+ }
+
+ for (const auto& dir : ld_library_paths_) {
+ if (file_is_in_dir(file, dir)) {
+ return true;
+ }
+ }
+
+ for (const auto& dir : default_library_paths_) {
+ if (file_is_in_dir(file, dir)) {
+ return true;
+ }
+ }
+
+ for (const auto& dir : permitted_paths_) {
+ if (file_is_under_dir(file, dir)) {
+ return true;
+ }
+ }
+
+ return false;
+}
+
diff --git a/linker/linker_namespaces.h b/linker/linker_namespaces.h
new file mode 100644
index 0000000..c1cee8e
--- /dev/null
+++ b/linker/linker_namespaces.h
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef __LINKER_NAMESPACES_H
+#define __LINKER_NAMESPACES_H
+
+#include "linker_common_types.h"
+
+#include <string>
+#include <vector>
+
+struct android_namespace_t {
+ public:
+ android_namespace_t() : name_(nullptr), is_isolated_(false) {}
+
+ const char* get_name() const { return name_; }
+ void set_name(const char* name) { name_ = name; }
+
+ bool is_isolated() const { return is_isolated_; }
+ void set_isolated(bool isolated) { is_isolated_ = isolated; }
+
+ const std::vector<std::string>& get_ld_library_paths() const {
+ return ld_library_paths_;
+ }
+ void set_ld_library_paths(std::vector<std::string>&& library_paths) {
+ ld_library_paths_ = library_paths;
+ }
+
+ const std::vector<std::string>& get_default_library_paths() const {
+ return default_library_paths_;
+ }
+ void set_default_library_paths(std::vector<std::string>&& library_paths) {
+ default_library_paths_ = library_paths;
+ }
+
+ const std::vector<std::string>& get_permitted_paths() const {
+ return permitted_paths_;
+ }
+ void set_permitted_paths(std::vector<std::string>&& permitted_paths) {
+ permitted_paths_ = permitted_paths;
+ }
+
+ void add_soinfo(soinfo* si) {
+ soinfo_list_.push_back(si);
+ }
+
+ void add_soinfos(const soinfo_list_t& soinfos) {
+ for (auto si : soinfos) {
+ add_soinfo(si);
+ }
+ }
+
+ void remove_soinfo(soinfo* si) {
+ soinfo_list_.remove_if([&](soinfo* candidate) {
+ return si == candidate;
+ });
+ }
+
+ const soinfo_list_t& soinfo_list() const { return soinfo_list_; }
+
+ // For isolated namespaces - checks if the file is on the search path;
+ // always returns true for not isolated namespace.
+ bool is_accessible(const std::string& path);
+
+ private:
+ const char* name_;
+ bool is_isolated_;
+ std::vector<std::string> ld_library_paths_;
+ std::vector<std::string> default_library_paths_;
+ std::vector<std::string> permitted_paths_;
+ soinfo_list_t soinfo_list_;
+
+ DISALLOW_COPY_AND_ASSIGN(android_namespace_t);
+};
+
+#endif /* __LINKER_NAMESPACES_H */
diff --git a/linker/linker_phdr.cpp b/linker/linker_phdr.cpp
new file mode 100644
index 0000000..bced722
--- /dev/null
+++ b/linker/linker_phdr.cpp
@@ -0,0 +1,1068 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "linker_phdr.h"
+
+#include <errno.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "linker.h"
+#include "linker_globals.h"
+#include "linker_debug.h"
+#include "linker_utils.h"
+
+#include "private/bionic_prctl.h"
+
+static int GetTargetElfMachine() {
+#if defined(__arm__)
+ return EM_ARM;
+#elif defined(__aarch64__)
+ return EM_AARCH64;
+#elif defined(__i386__)
+ return EM_386;
+#elif defined(__mips__)
+ return EM_MIPS;
+#elif defined(__x86_64__)
+ return EM_X86_64;
+#endif
+}
+
+/**
+ TECHNICAL NOTE ON ELF LOADING.
+
+ An ELF file's program header table contains one or more PT_LOAD
+ segments, which corresponds to portions of the file that need to
+ be mapped into the process' address space.
+
+ Each loadable segment has the following important properties:
+
+ p_offset -> segment file offset
+ p_filesz -> segment file size
+ p_memsz -> segment memory size (always >= p_filesz)
+ p_vaddr -> segment's virtual address
+ p_flags -> segment flags (e.g. readable, writable, executable)
+
+ We will ignore the p_paddr and p_align fields of ElfW(Phdr) for now.
+
+ The loadable segments can be seen as a list of [p_vaddr ... p_vaddr+p_memsz)
+ ranges of virtual addresses. A few rules apply:
+
+ - the virtual address ranges should not overlap.
+
+ - if a segment's p_filesz is smaller than its p_memsz, the extra bytes
+ between them should always be initialized to 0.
+
+ - ranges do not necessarily start or end at page boundaries. Two distinct
+ segments can have their start and end on the same page. In this case, the
+ page inherits the mapping flags of the latter segment.
+
+ Finally, the real load addrs of each segment is not p_vaddr. Instead the
+ loader decides where to load the first segment, then will load all others
+ relative to the first one to respect the initial range layout.
+
+ For example, consider the following list:
+
+ [ offset:0, filesz:0x4000, memsz:0x4000, vaddr:0x30000 ],
+ [ offset:0x4000, filesz:0x2000, memsz:0x8000, vaddr:0x40000 ],
+
+ This corresponds to two segments that cover these virtual address ranges:
+
+ 0x30000...0x34000
+ 0x40000...0x48000
+
+ If the loader decides to load the first segment at address 0xa0000000
+ then the segments' load address ranges will be:
+
+ 0xa0030000...0xa0034000
+ 0xa0040000...0xa0048000
+
+ In other words, all segments must be loaded at an address that has the same
+ constant offset from their p_vaddr value. This offset is computed as the
+ difference between the first segment's load address, and its p_vaddr value.
+
+ However, in practice, segments do _not_ start at page boundaries. Since we
+ can only memory-map at page boundaries, this means that the bias is
+ computed as:
+
+ load_bias = phdr0_load_address - PAGE_START(phdr0->p_vaddr)
+
+ (NOTE: The value must be used as a 32-bit unsigned integer, to deal with
+ possible wrap around UINT32_MAX for possible large p_vaddr values).
+
+ And that the phdr0_load_address must start at a page boundary, with
+ the segment's real content starting at:
+
+ phdr0_load_address + PAGE_OFFSET(phdr0->p_vaddr)
+
+ Note that ELF requires the following condition to make the mmap()-ing work:
+
+ PAGE_OFFSET(phdr0->p_vaddr) == PAGE_OFFSET(phdr0->p_offset)
+
+ The load_bias must be added to any p_vaddr value read from the ELF file to
+ determine the corresponding memory address.
+
+ **/
+
+#define MAYBE_MAP_FLAG(x, from, to) (((x) & (from)) ? (to) : 0)
+#define PFLAGS_TO_PROT(x) (MAYBE_MAP_FLAG((x), PF_X, PROT_EXEC) | \
+ MAYBE_MAP_FLAG((x), PF_R, PROT_READ) | \
+ MAYBE_MAP_FLAG((x), PF_W, PROT_WRITE))
+
+ElfReader::ElfReader()
+ : did_read_(false), did_load_(false), fd_(-1), file_offset_(0), file_size_(0), phdr_num_(0),
+ phdr_table_(nullptr), shdr_table_(nullptr), shdr_num_(0), dynamic_(nullptr), strtab_(nullptr),
+ strtab_size_(0), load_start_(nullptr), load_size_(0), load_bias_(0), loaded_phdr_(nullptr),
+ mapped_by_caller_(false) {
+}
+
+bool ElfReader::Read(const char* name, int fd, off64_t file_offset, off64_t file_size) {
+ CHECK(!did_read_);
+ CHECK(!did_load_);
+ name_ = name;
+ fd_ = fd;
+ file_offset_ = file_offset;
+ file_size_ = file_size;
+
+ if (ReadElfHeader() &&
+ VerifyElfHeader() &&
+ ReadProgramHeaders() &&
+ ReadSectionHeaders() &&
+ ReadDynamicSection()) {
+ did_read_ = true;
+ }
+
+ return did_read_;
+}
+
+bool ElfReader::Load(const android_dlextinfo* extinfo) {
+ CHECK(did_read_);
+ CHECK(!did_load_);
+ if (ReserveAddressSpace(extinfo) &&
+ LoadSegments() &&
+ FindPhdr()) {
+ did_load_ = true;
+ }
+
+ return did_load_;
+}
+
+const char* ElfReader::get_string(ElfW(Word) index) const {
+ CHECK(strtab_ != nullptr);
+ CHECK(index < strtab_size_);
+
+ return strtab_ + index;
+}
+
+bool ElfReader::ReadElfHeader() {
+ ssize_t rc = TEMP_FAILURE_RETRY(pread64(fd_, &header_, sizeof(header_), file_offset_));
+ if (rc < 0) {
+ DL_ERR("can't read file \"%s\": %s", name_.c_str(), strerror(errno));
+ return false;
+ }
+
+ if (rc != sizeof(header_)) {
+ DL_ERR("\"%s\" is too small to be an ELF executable: only found %zd bytes", name_.c_str(),
+ static_cast<size_t>(rc));
+ return false;
+ }
+ return true;
+}
+
+bool ElfReader::VerifyElfHeader() {
+ if (memcmp(header_.e_ident, ELFMAG, SELFMAG) != 0) {
+ DL_ERR("\"%s\" has bad ELF magic", name_.c_str());
+ return false;
+ }
+
+ // Try to give a clear diagnostic for ELF class mismatches, since they're
+ // an easy mistake to make during the 32-bit/64-bit transition period.
+ int elf_class = header_.e_ident[EI_CLASS];
+#if defined(__LP64__)
+ if (elf_class != ELFCLASS64) {
+ if (elf_class == ELFCLASS32) {
+ DL_ERR("\"%s\" is 32-bit instead of 64-bit", name_.c_str());
+ } else {
+ DL_ERR("\"%s\" has unknown ELF class: %d", name_.c_str(), elf_class);
+ }
+ return false;
+ }
+#else
+ if (elf_class != ELFCLASS32) {
+ if (elf_class == ELFCLASS64) {
+ DL_ERR("\"%s\" is 64-bit instead of 32-bit", name_.c_str());
+ } else {
+ DL_ERR("\"%s\" has unknown ELF class: %d", name_.c_str(), elf_class);
+ }
+ return false;
+ }
+#endif
+
+ if (header_.e_ident[EI_DATA] != ELFDATA2LSB) {
+ DL_ERR("\"%s\" not little-endian: %d", name_.c_str(), header_.e_ident[EI_DATA]);
+ return false;
+ }
+
+ if (header_.e_type != ET_DYN) {
+ DL_ERR("\"%s\" has unexpected e_type: %d", name_.c_str(), header_.e_type);
+ return false;
+ }
+
+ if (header_.e_version != EV_CURRENT) {
+ DL_ERR("\"%s\" has unexpected e_version: %d", name_.c_str(), header_.e_version);
+ return false;
+ }
+
+ if (header_.e_machine != GetTargetElfMachine()) {
+ DL_ERR("\"%s\" has unexpected e_machine: %d", name_.c_str(), header_.e_machine);
+ return false;
+ }
+
+ if (header_.e_shentsize != sizeof(ElfW(Shdr))) {
+ DL_ERR("\"%s\" has unsupported e_shentsize: 0x%x (expected 0x%zx)",
+ name_.c_str(), header_.e_shentsize, sizeof(ElfW(Shdr)));
+ return false;
+ }
+
+ if (header_.e_shstrndx == 0) {
+ DL_ERR("\"%s\" has invalid e_shstrndx", name_.c_str());
+ return false;
+ }
+
+ return true;
+}
+
+bool ElfReader::CheckFileRange(ElfW(Addr) offset, size_t size, size_t alignment) {
+ off64_t range_start;
+ off64_t range_end;
+
+ // Only header can be located at the 0 offset... This function called to
+ // check DYNSYM and DYNAMIC sections and phdr/shdr - none of them can be
+ // at offset 0.
+
+ return offset > 0 &&
+ safe_add(&range_start, file_offset_, offset) &&
+ safe_add(&range_end, range_start, size) &&
+ (range_start < file_size_) &&
+ (range_end <= file_size_) &&
+ ((offset % alignment) == 0);
+}
+
+// Loads the program header table from an ELF file into a read-only private
+// anonymous mmap-ed block.
+bool ElfReader::ReadProgramHeaders() {
+ phdr_num_ = header_.e_phnum;
+
+ // Like the kernel, we only accept program header tables that
+ // are smaller than 64KiB.
+ if (phdr_num_ < 1 || phdr_num_ > 65536/sizeof(ElfW(Phdr))) {
+ DL_ERR("\"%s\" has invalid e_phnum: %zd", name_.c_str(), phdr_num_);
+ return false;
+ }
+
+ // Boundary checks
+ size_t size = phdr_num_ * sizeof(ElfW(Phdr));
+ if (!CheckFileRange(header_.e_phoff, size, alignof(ElfW(Phdr)))) {
+ DL_ERR_AND_LOG("\"%s\" has invalid phdr offset/size: %zu/%zu",
+ name_.c_str(),
+ static_cast<size_t>(header_.e_phoff),
+ size);
+ return false;
+ }
+
+ if (!phdr_fragment_.Map(fd_, file_offset_, header_.e_phoff, size)) {
+ DL_ERR("\"%s\" phdr mmap failed: %s", name_.c_str(), strerror(errno));
+ return false;
+ }
+
+ phdr_table_ = static_cast<ElfW(Phdr)*>(phdr_fragment_.data());
+ return true;
+}
+
+bool ElfReader::ReadSectionHeaders() {
+ shdr_num_ = header_.e_shnum;
+
+ if (shdr_num_ == 0) {
+ DL_ERR_AND_LOG("\"%s\" has no section headers", name_.c_str());
+ return false;
+ }
+
+ size_t size = shdr_num_ * sizeof(ElfW(Shdr));
+ if (!CheckFileRange(header_.e_shoff, size, alignof(const ElfW(Shdr)))) {
+ DL_ERR_AND_LOG("\"%s\" has invalid shdr offset/size: %zu/%zu",
+ name_.c_str(),
+ static_cast<size_t>(header_.e_shoff),
+ size);
+ return false;
+ }
+
+ if (!shdr_fragment_.Map(fd_, file_offset_, header_.e_shoff, size)) {
+ DL_ERR("\"%s\" shdr mmap failed: %s", name_.c_str(), strerror(errno));
+ return false;
+ }
+
+ shdr_table_ = static_cast<const ElfW(Shdr)*>(shdr_fragment_.data());
+ return true;
+}
+
+bool ElfReader::ReadDynamicSection() {
+ // 1. Find .dynamic section (in section headers)
+ const ElfW(Shdr)* dynamic_shdr = nullptr;
+ for (size_t i = 0; i < shdr_num_; ++i) {
+ if (shdr_table_[i].sh_type == SHT_DYNAMIC) {
+ dynamic_shdr = &shdr_table_ [i];
+ break;
+ }
+ }
+
+ if (dynamic_shdr == nullptr) {
+ DL_ERR_AND_LOG("\"%s\" .dynamic section header was not found", name_.c_str());
+ return false;
+ }
+
+ // Make sure dynamic_shdr offset and size matches PT_DYNAMIC phdr
+ size_t pt_dynamic_offset = 0;
+ size_t pt_dynamic_filesz = 0;
+ for (size_t i = 0; i < phdr_num_; ++i) {
+ const ElfW(Phdr)* phdr = &phdr_table_[i];
+ if (phdr->p_type == PT_DYNAMIC) {
+ pt_dynamic_offset = phdr->p_offset;
+ pt_dynamic_filesz = phdr->p_filesz;
+ }
+ }
+
+ if (pt_dynamic_offset != dynamic_shdr->sh_offset) {
+ DL_ERR("\"%s\" .dynamic section has invalid offset: 0x%zx, "
+ "expected to match PT_DYNAMIC offset: 0x%zx",
+ name_.c_str(),
+ static_cast<size_t>(dynamic_shdr->sh_offset),
+ pt_dynamic_offset);
+ return false;
+ }
+
+ if (pt_dynamic_filesz != dynamic_shdr->sh_size) {
+ DL_ERR("\"%s\" .dynamic section has invalid size: 0x%zx, "
+ "expected to match PT_DYNAMIC filesz: 0x%zx",
+ name_.c_str(),
+ static_cast<size_t>(dynamic_shdr->sh_size),
+ pt_dynamic_filesz);
+ return false;
+ }
+
+ if (dynamic_shdr->sh_link >= shdr_num_) {
+ DL_ERR_AND_LOG("\"%s\" .dynamic section has invalid sh_link: %d",
+ name_.c_str(),
+ dynamic_shdr->sh_link);
+ return false;
+ }
+
+ const ElfW(Shdr)* strtab_shdr = &shdr_table_[dynamic_shdr->sh_link];
+
+ if (strtab_shdr->sh_type != SHT_STRTAB) {
+ DL_ERR_AND_LOG("\"%s\" .dynamic section has invalid link(%d) sh_type: %d (expected SHT_STRTAB)",
+ name_.c_str(), dynamic_shdr->sh_link, strtab_shdr->sh_type);
+ return false;
+ }
+
+ if (!CheckFileRange(dynamic_shdr->sh_offset, dynamic_shdr->sh_size, alignof(const ElfW(Dyn)))) {
+ DL_ERR_AND_LOG("\"%s\" has invalid offset/size of .dynamic section", name_.c_str());
+ return false;
+ }
+
+ if (!dynamic_fragment_.Map(fd_, file_offset_, dynamic_shdr->sh_offset, dynamic_shdr->sh_size)) {
+ DL_ERR("\"%s\" dynamic section mmap failed: %s", name_.c_str(), strerror(errno));
+ return false;
+ }
+
+ dynamic_ = static_cast<const ElfW(Dyn)*>(dynamic_fragment_.data());
+
+ if (!CheckFileRange(strtab_shdr->sh_offset, strtab_shdr->sh_size, alignof(const char))) {
+ DL_ERR_AND_LOG("\"%s\" has invalid offset/size of the .strtab section linked from .dynamic section",
+ name_.c_str());
+ return false;
+ }
+
+ if (!strtab_fragment_.Map(fd_, file_offset_, strtab_shdr->sh_offset, strtab_shdr->sh_size)) {
+ DL_ERR("\"%s\" strtab section mmap failed: %s", name_.c_str(), strerror(errno));
+ return false;
+ }
+
+ strtab_ = static_cast<const char*>(strtab_fragment_.data());
+ strtab_size_ = strtab_fragment_.size();
+ return true;
+}
+
+/* Returns the size of the extent of all the possibly non-contiguous
+ * loadable segments in an ELF program header table. This corresponds
+ * to the page-aligned size in bytes that needs to be reserved in the
+ * process' address space. If there are no loadable segments, 0 is
+ * returned.
+ *
+ * If out_min_vaddr or out_max_vaddr are not null, they will be
+ * set to the minimum and maximum addresses of pages to be reserved,
+ * or 0 if there is nothing to load.
+ */
+size_t phdr_table_get_load_size(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr)* out_min_vaddr,
+ ElfW(Addr)* out_max_vaddr) {
+ ElfW(Addr) min_vaddr = UINTPTR_MAX;
+ ElfW(Addr) max_vaddr = 0;
+
+ bool found_pt_load = false;
+ for (size_t i = 0; i < phdr_count; ++i) {
+ const ElfW(Phdr)* phdr = &phdr_table[i];
+
+ if (phdr->p_type != PT_LOAD) {
+ continue;
+ }
+ found_pt_load = true;
+
+ if (phdr->p_vaddr < min_vaddr) {
+ min_vaddr = phdr->p_vaddr;
+ }
+
+ if (phdr->p_vaddr + phdr->p_memsz > max_vaddr) {
+ max_vaddr = phdr->p_vaddr + phdr->p_memsz;
+ }
+ }
+ if (!found_pt_load) {
+ min_vaddr = 0;
+ }
+
+ min_vaddr = PAGE_START(min_vaddr);
+ max_vaddr = PAGE_END(max_vaddr);
+
+ if (out_min_vaddr != nullptr) {
+ *out_min_vaddr = min_vaddr;
+ }
+ if (out_max_vaddr != nullptr) {
+ *out_max_vaddr = max_vaddr;
+ }
+ return max_vaddr - min_vaddr;
+}
+
+// Reserve a virtual address range such that if it's limits were extended to the next 2**align
+// boundary, it would not overlap with any existing mappings.
+static void* ReserveAligned(void* hint, size_t size, size_t align) {
+ int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS;
+ // Address hint is only used in Art for the image mapping, and it is pretty important. Don't mess
+ // with it.
+ // FIXME: try an aligned allocation and fall back to plain mmap() if the former does not provide a
+ // mapping at the requested address?
+ if (align == PAGE_SIZE || hint != nullptr) {
+ void* mmap_ptr = mmap(hint, size, PROT_NONE, mmap_flags, -1, 0);
+ if (mmap_ptr == MAP_FAILED) {
+ return nullptr;
+ }
+ return mmap_ptr;
+ }
+
+ // Allocate enough space so that the end of the desired region aligned up is still inside the
+ // mapping.
+ size_t mmap_size = align_up(size, align) + align - PAGE_SIZE;
+ uint8_t* mmap_ptr =
+ reinterpret_cast<uint8_t*>(mmap(nullptr, mmap_size, PROT_NONE, mmap_flags, -1, 0));
+ if (mmap_ptr == MAP_FAILED) {
+ return nullptr;
+ }
+
+ uint8_t* first = align_up(mmap_ptr, align);
+ uint8_t* last = align_down(mmap_ptr + mmap_size, align) - size;
+ size_t n = arc4random_uniform((last - first) / PAGE_SIZE + 1);
+ uint8_t* start = first + n * PAGE_SIZE;
+ munmap(mmap_ptr, start - mmap_ptr);
+ munmap(start + size, mmap_ptr + mmap_size - (start + size));
+ return start;
+}
+
+// Reserve a virtual address range big enough to hold all loadable
+// segments of a program header table. This is done by creating a
+// private anonymous mmap() with PROT_NONE.
+bool ElfReader::ReserveAddressSpace(const android_dlextinfo* extinfo) {
+ ElfW(Addr) min_vaddr;
+ load_size_ = phdr_table_get_load_size(phdr_table_, phdr_num_, &min_vaddr);
+ if (load_size_ == 0) {
+ DL_ERR("\"%s\" has no loadable segments", name_.c_str());
+ return false;
+ }
+
+ uint8_t* addr = reinterpret_cast<uint8_t*>(min_vaddr);
+ void* start;
+ size_t reserved_size = 0;
+ bool reserved_hint = true;
+ bool strict_hint = false;
+ // Assume position independent executable by default.
+ void* mmap_hint = nullptr;
+
+ if (extinfo != nullptr) {
+ if (extinfo->flags & ANDROID_DLEXT_RESERVED_ADDRESS) {
+ reserved_size = extinfo->reserved_size;
+ reserved_hint = false;
+ } else if (extinfo->flags & ANDROID_DLEXT_RESERVED_ADDRESS_HINT) {
+ reserved_size = extinfo->reserved_size;
+ }
+
+ if (addr != nullptr && (extinfo->flags & ANDROID_DLEXT_FORCE_FIXED_VADDR) != 0) {
+ mmap_hint = addr;
+ } else if ((extinfo->flags & ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS) != 0) {
+ mmap_hint = extinfo->reserved_addr;
+ strict_hint = true;
+ }
+ }
+
+ if (load_size_ > reserved_size) {
+ if (!reserved_hint) {
+ DL_ERR("reserved address space %zd smaller than %zd bytes needed for \"%s\"",
+ reserved_size - load_size_, load_size_, name_.c_str());
+ return false;
+ }
+ start = ReserveAligned(mmap_hint, load_size_, kLibraryAlignment);
+ if (start == nullptr) {
+ DL_ERR("couldn't reserve %zd bytes of address space for \"%s\"", load_size_, name_.c_str());
+ return false;
+ }
+ if (strict_hint && (start != mmap_hint)) {
+ munmap(start, load_size_);
+ DL_ERR("couldn't reserve %zd bytes of address space at %p for \"%s\"",
+ load_size_, mmap_hint, name_.c_str());
+ return false;
+ }
+ } else {
+ start = extinfo->reserved_addr;
+ mapped_by_caller_ = true;
+ }
+
+ load_start_ = start;
+ load_bias_ = reinterpret_cast<uint8_t*>(start) - addr;
+ return true;
+}
+
+bool ElfReader::LoadSegments() {
+ for (size_t i = 0; i < phdr_num_; ++i) {
+ const ElfW(Phdr)* phdr = &phdr_table_[i];
+
+ if (phdr->p_type != PT_LOAD) {
+ continue;
+ }
+
+ // Segment addresses in memory.
+ ElfW(Addr) seg_start = phdr->p_vaddr + load_bias_;
+ ElfW(Addr) seg_end = seg_start + phdr->p_memsz;
+
+ ElfW(Addr) seg_page_start = PAGE_START(seg_start);
+ ElfW(Addr) seg_page_end = PAGE_END(seg_end);
+
+ ElfW(Addr) seg_file_end = seg_start + phdr->p_filesz;
+
+ // File offsets.
+ ElfW(Addr) file_start = phdr->p_offset;
+ ElfW(Addr) file_end = file_start + phdr->p_filesz;
+
+ ElfW(Addr) file_page_start = PAGE_START(file_start);
+ ElfW(Addr) file_length = file_end - file_page_start;
+
+ if (file_size_ <= 0) {
+ DL_ERR("\"%s\" invalid file size: %" PRId64, name_.c_str(), file_size_);
+ return false;
+ }
+
+ if (file_end > static_cast<size_t>(file_size_)) {
+ DL_ERR("invalid ELF file \"%s\" load segment[%zd]:"
+ " p_offset (%p) + p_filesz (%p) ( = %p) past end of file (0x%" PRIx64 ")",
+ name_.c_str(), i, reinterpret_cast<void*>(phdr->p_offset),
+ reinterpret_cast<void*>(phdr->p_filesz),
+ reinterpret_cast<void*>(file_end), file_size_);
+ return false;
+ }
+
+ if (file_length != 0) {
+ int prot = PFLAGS_TO_PROT(phdr->p_flags);
+ // W + E PT_LOAD segments are not allowed.
+ if ((prot & (PROT_EXEC | PROT_WRITE)) == (PROT_EXEC | PROT_WRITE)) {
+ DL_ERR_AND_LOG("\"%s\": W + E load segments are not allowed", name_.c_str());
+ return false;
+ }
+
+ void* seg_addr = mmap64(reinterpret_cast<void*>(seg_page_start),
+ file_length,
+ prot,
+ MAP_FIXED|MAP_PRIVATE,
+ fd_,
+ file_offset_ + file_page_start);
+ if (seg_addr == MAP_FAILED) {
+ DL_ERR("couldn't map \"%s\" segment %zd: %s", name_.c_str(), i, strerror(errno));
+ return false;
+ }
+ }
+
+ // if the segment is writable, and does not end on a page boundary,
+ // zero-fill it until the page limit.
+ if ((phdr->p_flags & PF_W) != 0 && PAGE_OFFSET(seg_file_end) > 0) {
+ memset(reinterpret_cast<void*>(seg_file_end), 0, PAGE_SIZE - PAGE_OFFSET(seg_file_end));
+ }
+
+ seg_file_end = PAGE_END(seg_file_end);
+
+ // seg_file_end is now the first page address after the file
+ // content. If seg_end is larger, we need to zero anything
+ // between them. This is done by using a private anonymous
+ // map for all extra pages.
+ if (seg_page_end > seg_file_end) {
+ size_t zeromap_size = seg_page_end - seg_file_end;
+ void* zeromap = mmap(reinterpret_cast<void*>(seg_file_end),
+ zeromap_size,
+ PFLAGS_TO_PROT(phdr->p_flags),
+ MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE,
+ -1,
+ 0);
+ if (zeromap == MAP_FAILED) {
+ DL_ERR("couldn't zero fill \"%s\" gap: %s", name_.c_str(), strerror(errno));
+ return false;
+ }
+
+ prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, zeromap, zeromap_size, ".bss");
+ }
+ }
+ return true;
+}
+
+/* Used internally. Used to set the protection bits of all loaded segments
+ * with optional extra flags (i.e. really PROT_WRITE). Used by
+ * phdr_table_protect_segments and phdr_table_unprotect_segments.
+ */
+static int _phdr_table_set_load_prot(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias, int extra_prot_flags) {
+ const ElfW(Phdr)* phdr = phdr_table;
+ const ElfW(Phdr)* phdr_limit = phdr + phdr_count;
+
+ for (; phdr < phdr_limit; phdr++) {
+ if (phdr->p_type != PT_LOAD || (phdr->p_flags & PF_W) != 0) {
+ continue;
+ }
+
+ ElfW(Addr) seg_page_start = PAGE_START(phdr->p_vaddr) + load_bias;
+ ElfW(Addr) seg_page_end = PAGE_END(phdr->p_vaddr + phdr->p_memsz) + load_bias;
+
+ int prot = PFLAGS_TO_PROT(phdr->p_flags);
+ if ((extra_prot_flags & PROT_WRITE) != 0) {
+ // make sure we're never simultaneously writable / executable
+ prot &= ~PROT_EXEC;
+ }
+
+ int ret = mprotect(reinterpret_cast<void*>(seg_page_start),
+ seg_page_end - seg_page_start,
+ prot | extra_prot_flags);
+ if (ret < 0) {
+ return -1;
+ }
+ }
+ return 0;
+}
+
+/* Restore the original protection modes for all loadable segments.
+ * You should only call this after phdr_table_unprotect_segments and
+ * applying all relocations.
+ *
+ * Input:
+ * phdr_table -> program header table
+ * phdr_count -> number of entries in tables
+ * load_bias -> load bias
+ * Return:
+ * 0 on error, -1 on failure (error code in errno).
+ */
+int phdr_table_protect_segments(const ElfW(Phdr)* phdr_table,
+ size_t phdr_count, ElfW(Addr) load_bias) {
+ return _phdr_table_set_load_prot(phdr_table, phdr_count, load_bias, 0);
+}
+
+/* Change the protection of all loaded segments in memory to writable.
+ * This is useful before performing relocations. Once completed, you
+ * will have to call phdr_table_protect_segments to restore the original
+ * protection flags on all segments.
+ *
+ * Note that some writable segments can also have their content turned
+ * to read-only by calling phdr_table_protect_gnu_relro. This is no
+ * performed here.
+ *
+ * Input:
+ * phdr_table -> program header table
+ * phdr_count -> number of entries in tables
+ * load_bias -> load bias
+ * Return:
+ * 0 on error, -1 on failure (error code in errno).
+ */
+int phdr_table_unprotect_segments(const ElfW(Phdr)* phdr_table,
+ size_t phdr_count, ElfW(Addr) load_bias) {
+ return _phdr_table_set_load_prot(phdr_table, phdr_count, load_bias, PROT_WRITE);
+}
+
+/* Used internally by phdr_table_protect_gnu_relro and
+ * phdr_table_unprotect_gnu_relro.
+ */
+static int _phdr_table_set_gnu_relro_prot(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias, int prot_flags) {
+ const ElfW(Phdr)* phdr = phdr_table;
+ const ElfW(Phdr)* phdr_limit = phdr + phdr_count;
+
+ for (phdr = phdr_table; phdr < phdr_limit; phdr++) {
+ if (phdr->p_type != PT_GNU_RELRO) {
+ continue;
+ }
+
+ // Tricky: what happens when the relro segment does not start
+ // or end at page boundaries? We're going to be over-protective
+ // here and put every page touched by the segment as read-only.
+
+ // This seems to match Ian Lance Taylor's description of the
+ // feature at http://www.airs.com/blog/archives/189.
+
+ // Extract:
+ // Note that the current dynamic linker code will only work
+ // correctly if the PT_GNU_RELRO segment starts on a page
+ // boundary. This is because the dynamic linker rounds the
+ // p_vaddr field down to the previous page boundary. If
+ // there is anything on the page which should not be read-only,
+ // the program is likely to fail at runtime. So in effect the
+ // linker must only emit a PT_GNU_RELRO segment if it ensures
+ // that it starts on a page boundary.
+ ElfW(Addr) seg_page_start = PAGE_START(phdr->p_vaddr) + load_bias;
+ ElfW(Addr) seg_page_end = PAGE_END(phdr->p_vaddr + phdr->p_memsz) + load_bias;
+
+ int ret = mprotect(reinterpret_cast<void*>(seg_page_start),
+ seg_page_end - seg_page_start,
+ prot_flags);
+ if (ret < 0) {
+ return -1;
+ }
+ }
+ return 0;
+}
+
+/* Apply GNU relro protection if specified by the program header. This will
+ * turn some of the pages of a writable PT_LOAD segment to read-only, as
+ * specified by one or more PT_GNU_RELRO segments. This must be always
+ * performed after relocations.
+ *
+ * The areas typically covered are .got and .data.rel.ro, these are
+ * read-only from the program's POV, but contain absolute addresses
+ * that need to be relocated before use.
+ *
+ * Input:
+ * phdr_table -> program header table
+ * phdr_count -> number of entries in tables
+ * load_bias -> load bias
+ * Return:
+ * 0 on error, -1 on failure (error code in errno).
+ */
+int phdr_table_protect_gnu_relro(const ElfW(Phdr)* phdr_table,
+ size_t phdr_count, ElfW(Addr) load_bias) {
+ return _phdr_table_set_gnu_relro_prot(phdr_table, phdr_count, load_bias, PROT_READ);
+}
+
+/* Serialize the GNU relro segments to the given file descriptor. This can be
+ * performed after relocations to allow another process to later share the
+ * relocated segment, if it was loaded at the same address.
+ *
+ * Input:
+ * phdr_table -> program header table
+ * phdr_count -> number of entries in tables
+ * load_bias -> load bias
+ * fd -> writable file descriptor to use
+ * Return:
+ * 0 on error, -1 on failure (error code in errno).
+ */
+int phdr_table_serialize_gnu_relro(const ElfW(Phdr)* phdr_table,
+ size_t phdr_count,
+ ElfW(Addr) load_bias,
+ int fd) {
+ const ElfW(Phdr)* phdr = phdr_table;
+ const ElfW(Phdr)* phdr_limit = phdr + phdr_count;
+ ssize_t file_offset = 0;
+
+ for (phdr = phdr_table; phdr < phdr_limit; phdr++) {
+ if (phdr->p_type != PT_GNU_RELRO) {
+ continue;
+ }
+
+ ElfW(Addr) seg_page_start = PAGE_START(phdr->p_vaddr) + load_bias;
+ ElfW(Addr) seg_page_end = PAGE_END(phdr->p_vaddr + phdr->p_memsz) + load_bias;
+ ssize_t size = seg_page_end - seg_page_start;
+
+ ssize_t written = TEMP_FAILURE_RETRY(write(fd, reinterpret_cast<void*>(seg_page_start), size));
+ if (written != size) {
+ return -1;
+ }
+ void* map = mmap(reinterpret_cast<void*>(seg_page_start), size, PROT_READ,
+ MAP_PRIVATE|MAP_FIXED, fd, file_offset);
+ if (map == MAP_FAILED) {
+ return -1;
+ }
+ file_offset += size;
+ }
+ return 0;
+}
+
+/* Where possible, replace the GNU relro segments with mappings of the given
+ * file descriptor. This can be performed after relocations to allow a file
+ * previously created by phdr_table_serialize_gnu_relro in another process to
+ * replace the dirty relocated pages, saving memory, if it was loaded at the
+ * same address. We have to compare the data before we map over it, since some
+ * parts of the relro segment may not be identical due to other libraries in
+ * the process being loaded at different addresses.
+ *
+ * Input:
+ * phdr_table -> program header table
+ * phdr_count -> number of entries in tables
+ * load_bias -> load bias
+ * fd -> readable file descriptor to use
+ * Return:
+ * 0 on error, -1 on failure (error code in errno).
+ */
+int phdr_table_map_gnu_relro(const ElfW(Phdr)* phdr_table,
+ size_t phdr_count,
+ ElfW(Addr) load_bias,
+ int fd) {
+ // Map the file at a temporary location so we can compare its contents.
+ struct stat file_stat;
+ if (TEMP_FAILURE_RETRY(fstat(fd, &file_stat)) != 0) {
+ return -1;
+ }
+ off_t file_size = file_stat.st_size;
+ void* temp_mapping = nullptr;
+ if (file_size > 0) {
+ temp_mapping = mmap(nullptr, file_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (temp_mapping == MAP_FAILED) {
+ return -1;
+ }
+ }
+ size_t file_offset = 0;
+
+ // Iterate over the relro segments and compare/remap the pages.
+ const ElfW(Phdr)* phdr = phdr_table;
+ const ElfW(Phdr)* phdr_limit = phdr + phdr_count;
+
+ for (phdr = phdr_table; phdr < phdr_limit; phdr++) {
+ if (phdr->p_type != PT_GNU_RELRO) {
+ continue;
+ }
+
+ ElfW(Addr) seg_page_start = PAGE_START(phdr->p_vaddr) + load_bias;
+ ElfW(Addr) seg_page_end = PAGE_END(phdr->p_vaddr + phdr->p_memsz) + load_bias;
+
+ char* file_base = static_cast<char*>(temp_mapping) + file_offset;
+ char* mem_base = reinterpret_cast<char*>(seg_page_start);
+ size_t match_offset = 0;
+ size_t size = seg_page_end - seg_page_start;
+
+ if (file_size - file_offset < size) {
+ // File is too short to compare to this segment. The contents are likely
+ // different as well (it's probably for a different library version) so
+ // just don't bother checking.
+ break;
+ }
+
+ while (match_offset < size) {
+ // Skip over dissimilar pages.
+ while (match_offset < size &&
+ memcmp(mem_base + match_offset, file_base + match_offset, PAGE_SIZE) != 0) {
+ match_offset += PAGE_SIZE;
+ }
+
+ // Count similar pages.
+ size_t mismatch_offset = match_offset;
+ while (mismatch_offset < size &&
+ memcmp(mem_base + mismatch_offset, file_base + mismatch_offset, PAGE_SIZE) == 0) {
+ mismatch_offset += PAGE_SIZE;
+ }
+
+ // Map over similar pages.
+ if (mismatch_offset > match_offset) {
+ void* map = mmap(mem_base + match_offset, mismatch_offset - match_offset,
+ PROT_READ, MAP_PRIVATE|MAP_FIXED, fd, match_offset);
+ if (map == MAP_FAILED) {
+ munmap(temp_mapping, file_size);
+ return -1;
+ }
+ }
+
+ match_offset = mismatch_offset;
+ }
+
+ // Add to the base file offset in case there are multiple relro segments.
+ file_offset += size;
+ }
+ munmap(temp_mapping, file_size);
+ return 0;
+}
+
+
+#if defined(__arm__)
+
+# ifndef PT_ARM_EXIDX
+# define PT_ARM_EXIDX 0x70000001 /* .ARM.exidx segment */
+# endif
+
+/* Return the address and size of the .ARM.exidx section in memory,
+ * if present.
+ *
+ * Input:
+ * phdr_table -> program header table
+ * phdr_count -> number of entries in tables
+ * load_bias -> load bias
+ * Output:
+ * arm_exidx -> address of table in memory (null on failure).
+ * arm_exidx_count -> number of items in table (0 on failure).
+ * Return:
+ * 0 on error, -1 on failure (_no_ error code in errno)
+ */
+int phdr_table_get_arm_exidx(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias,
+ ElfW(Addr)** arm_exidx, size_t* arm_exidx_count) {
+ const ElfW(Phdr)* phdr = phdr_table;
+ const ElfW(Phdr)* phdr_limit = phdr + phdr_count;
+
+ for (phdr = phdr_table; phdr < phdr_limit; phdr++) {
+ if (phdr->p_type != PT_ARM_EXIDX) {
+ continue;
+ }
+
+ *arm_exidx = reinterpret_cast<ElfW(Addr)*>(load_bias + phdr->p_vaddr);
+ *arm_exidx_count = phdr->p_memsz / 8;
+ return 0;
+ }
+ *arm_exidx = nullptr;
+ *arm_exidx_count = 0;
+ return -1;
+}
+#endif
+
+/* Return the address and size of the ELF file's .dynamic section in memory,
+ * or null if missing.
+ *
+ * Input:
+ * phdr_table -> program header table
+ * phdr_count -> number of entries in tables
+ * load_bias -> load bias
+ * Output:
+ * dynamic -> address of table in memory (null on failure).
+ * dynamic_flags -> protection flags for section (unset on failure)
+ * Return:
+ * void
+ */
+void phdr_table_get_dynamic_section(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias, ElfW(Dyn)** dynamic,
+ ElfW(Word)* dynamic_flags) {
+ *dynamic = nullptr;
+ for (size_t i = 0; i<phdr_count; ++i) {
+ const ElfW(Phdr)& phdr = phdr_table[i];
+ if (phdr.p_type == PT_DYNAMIC) {
+ *dynamic = reinterpret_cast<ElfW(Dyn)*>(load_bias + phdr.p_vaddr);
+ if (dynamic_flags) {
+ *dynamic_flags = phdr.p_flags;
+ }
+ return;
+ }
+ }
+}
+
+/* Return the program interpreter string, or nullptr if missing.
+ *
+ * Input:
+ * phdr_table -> program header table
+ * phdr_count -> number of entries in tables
+ * load_bias -> load bias
+ * Return:
+ * pointer to the program interpreter string.
+ */
+const char* phdr_table_get_interpreter_name(const ElfW(Phdr) * phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias) {
+ for (size_t i = 0; i<phdr_count; ++i) {
+ const ElfW(Phdr)& phdr = phdr_table[i];
+ if (phdr.p_type == PT_INTERP) {
+ return reinterpret_cast<const char*>(load_bias + phdr.p_vaddr);
+ }
+ }
+ return nullptr;
+}
+
+// Sets loaded_phdr_ to the address of the program header table as it appears
+// in the loaded segments in memory. This is in contrast with phdr_table_,
+// which is temporary and will be released before the library is relocated.
+bool ElfReader::FindPhdr() {
+ const ElfW(Phdr)* phdr_limit = phdr_table_ + phdr_num_;
+
+ // If there is a PT_PHDR, use it directly.
+ for (const ElfW(Phdr)* phdr = phdr_table_; phdr < phdr_limit; ++phdr) {
+ if (phdr->p_type == PT_PHDR) {
+ return CheckPhdr(load_bias_ + phdr->p_vaddr);
+ }
+ }
+
+ // Otherwise, check the first loadable segment. If its file offset
+ // is 0, it starts with the ELF header, and we can trivially find the
+ // loaded program header from it.
+ for (const ElfW(Phdr)* phdr = phdr_table_; phdr < phdr_limit; ++phdr) {
+ if (phdr->p_type == PT_LOAD) {
+ if (phdr->p_offset == 0) {
+ ElfW(Addr) elf_addr = load_bias_ + phdr->p_vaddr;
+ const ElfW(Ehdr)* ehdr = reinterpret_cast<const ElfW(Ehdr)*>(elf_addr);
+ ElfW(Addr) offset = ehdr->e_phoff;
+ return CheckPhdr(reinterpret_cast<ElfW(Addr)>(ehdr) + offset);
+ }
+ break;
+ }
+ }
+
+ DL_ERR("can't find loaded phdr for \"%s\"", name_.c_str());
+ return false;
+}
+
+// Ensures that our program header is actually within a loadable
+// segment. This should help catch badly-formed ELF files that
+// would cause the linker to crash later when trying to access it.
+bool ElfReader::CheckPhdr(ElfW(Addr) loaded) {
+ const ElfW(Phdr)* phdr_limit = phdr_table_ + phdr_num_;
+ ElfW(Addr) loaded_end = loaded + (phdr_num_ * sizeof(ElfW(Phdr)));
+ for (const ElfW(Phdr)* phdr = phdr_table_; phdr < phdr_limit; ++phdr) {
+ if (phdr->p_type != PT_LOAD) {
+ continue;
+ }
+ ElfW(Addr) seg_start = phdr->p_vaddr + load_bias_;
+ ElfW(Addr) seg_end = phdr->p_filesz + seg_start;
+ if (seg_start <= loaded && loaded_end <= seg_end) {
+ loaded_phdr_ = reinterpret_cast<const ElfW(Phdr)*>(loaded);
+ return true;
+ }
+ }
+ DL_ERR("\"%s\" loaded phdr %p not in loadable segment",
+ name_.c_str(), reinterpret_cast<void*>(loaded));
+ return false;
+}
diff --git a/linker/linker_phdr.h b/linker/linker_phdr.h
new file mode 100644
index 0000000..d6276ed
--- /dev/null
+++ b/linker/linker_phdr.h
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#ifndef LINKER_PHDR_H
+#define LINKER_PHDR_H
+
+/* Declarations related to the ELF program header table and segments.
+ *
+ * The design goal is to provide an API that is as close as possible
+ * to the ELF spec, and does not depend on linker-specific data
+ * structures (e.g. the exact layout of struct soinfo).
+ */
+
+#include "linker.h"
+#include "linker_mapped_file_fragment.h"
+
+class ElfReader {
+ public:
+ ElfReader();
+
+ bool Read(const char* name, int fd, off64_t file_offset, off64_t file_size);
+ bool Load(const android_dlextinfo* extinfo);
+
+ const char* name() const { return name_.c_str(); }
+ size_t phdr_count() const { return phdr_num_; }
+ ElfW(Addr) load_start() const { return reinterpret_cast<ElfW(Addr)>(load_start_); }
+ size_t load_size() const { return load_size_; }
+ ElfW(Addr) load_bias() const { return load_bias_; }
+ const ElfW(Phdr)* loaded_phdr() const { return loaded_phdr_; }
+ const ElfW(Dyn)* dynamic() const { return dynamic_; }
+ const char* get_string(ElfW(Word) index) const;
+ bool is_mapped_by_caller() const { return mapped_by_caller_; }
+
+ private:
+ bool ReadElfHeader();
+ bool VerifyElfHeader();
+ bool ReadProgramHeaders();
+ bool ReadSectionHeaders();
+ bool ReadDynamicSection();
+ bool ReserveAddressSpace(const android_dlextinfo* extinfo);
+ bool LoadSegments();
+ bool FindPhdr();
+ bool CheckPhdr(ElfW(Addr));
+ bool CheckFileRange(ElfW(Addr) offset, size_t size, size_t alignment);
+
+ bool did_read_;
+ bool did_load_;
+ std::string name_;
+ int fd_;
+ off64_t file_offset_;
+ off64_t file_size_;
+
+ ElfW(Ehdr) header_;
+ size_t phdr_num_;
+
+ MappedFileFragment phdr_fragment_;
+ const ElfW(Phdr)* phdr_table_;
+
+ MappedFileFragment shdr_fragment_;
+ const ElfW(Shdr)* shdr_table_;
+ size_t shdr_num_;
+
+ MappedFileFragment dynamic_fragment_;
+ const ElfW(Dyn)* dynamic_;
+
+ MappedFileFragment strtab_fragment_;
+ const char* strtab_;
+ size_t strtab_size_;
+
+ // First page of reserved address space.
+ void* load_start_;
+ // Size in bytes of reserved address space.
+ size_t load_size_;
+ // Load bias.
+ ElfW(Addr) load_bias_;
+
+ // Loaded phdr.
+ const ElfW(Phdr)* loaded_phdr_;
+
+ // Is map owned by the caller
+ bool mapped_by_caller_;
+};
+
+size_t phdr_table_get_load_size(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr)* min_vaddr = nullptr, ElfW(Addr)* max_vaddr = nullptr);
+
+int phdr_table_protect_segments(const ElfW(Phdr)* phdr_table,
+ size_t phdr_count, ElfW(Addr) load_bias);
+
+int phdr_table_unprotect_segments(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias);
+
+int phdr_table_protect_gnu_relro(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias);
+
+int phdr_table_serialize_gnu_relro(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias, int fd);
+
+int phdr_table_map_gnu_relro(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias, int fd);
+
+#if defined(__arm__)
+int phdr_table_get_arm_exidx(const ElfW(Phdr)* phdr_table, size_t phdr_count, ElfW(Addr) load_bias,
+ ElfW(Addr)** arm_exidx, size_t* arm_exidix_count);
+#endif
+
+void phdr_table_get_dynamic_section(const ElfW(Phdr)* phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias, ElfW(Dyn)** dynamic,
+ ElfW(Word)* dynamic_flags);
+
+const char* phdr_table_get_interpreter_name(const ElfW(Phdr) * phdr_table, size_t phdr_count,
+ ElfW(Addr) load_bias);
+
+#endif /* LINKER_PHDR_H */
diff --git a/linker/linker_reloc_iterators.h b/linker/linker_reloc_iterators.h
new file mode 100644
index 0000000..f28c0e0
--- /dev/null
+++ b/linker/linker_reloc_iterators.h
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LINKER_RELOC_ITERATORS_H
+#define __LINKER_RELOC_ITERATORS_H
+
+#include "linker.h"
+
+#include <string.h>
+
+const size_t RELOCATION_GROUPED_BY_INFO_FLAG = 1;
+const size_t RELOCATION_GROUPED_BY_OFFSET_DELTA_FLAG = 2;
+const size_t RELOCATION_GROUPED_BY_ADDEND_FLAG = 4;
+const size_t RELOCATION_GROUP_HAS_ADDEND_FLAG = 8;
+
+class plain_reloc_iterator {
+#if defined(USE_RELA)
+ typedef ElfW(Rela) rel_t;
+#else
+ typedef ElfW(Rel) rel_t;
+#endif
+ public:
+ plain_reloc_iterator(rel_t* rel_array, size_t count)
+ : begin_(rel_array), end_(begin_ + count), current_(begin_) {}
+
+ bool has_next() {
+ return current_ < end_;
+ }
+
+ rel_t* next() {
+ return current_++;
+ }
+ private:
+ rel_t* const begin_;
+ rel_t* const end_;
+ rel_t* current_;
+
+ DISALLOW_COPY_AND_ASSIGN(plain_reloc_iterator);
+};
+
+template <typename decoder_t>
+class packed_reloc_iterator {
+#if defined(USE_RELA)
+ typedef ElfW(Rela) rel_t;
+#else
+ typedef ElfW(Rel) rel_t;
+#endif
+ public:
+ explicit packed_reloc_iterator(decoder_t&& decoder)
+ : decoder_(decoder) {
+ // initialize fields
+ memset(&reloc_, 0, sizeof(reloc_));
+ relocation_count_ = decoder_.pop_front();
+ reloc_.r_offset = decoder_.pop_front();
+ relocation_index_ = 0;
+ relocation_group_index_ = 0;
+ group_size_ = 0;
+ }
+
+ bool has_next() const {
+ return relocation_index_ < relocation_count_;
+ }
+
+ rel_t* next() {
+ if (relocation_group_index_ == group_size_) {
+ if (!read_group_fields()) {
+ // Iterator is inconsistent state; it should not be called again
+ // but in case it is let's make sure has_next() returns false.
+ relocation_index_ = relocation_count_ = 0;
+ return nullptr;
+ }
+ }
+
+ if (is_relocation_grouped_by_offset_delta()) {
+ reloc_.r_offset += group_r_offset_delta_;
+ } else {
+ reloc_.r_offset += decoder_.pop_front();
+ }
+
+ if (!is_relocation_grouped_by_info()) {
+ reloc_.r_info = decoder_.pop_front();
+ }
+
+#if defined(USE_RELA)
+ if (is_relocation_group_has_addend() &&
+ !is_relocation_grouped_by_addend()) {
+ reloc_.r_addend += decoder_.pop_front();
+ }
+#endif
+
+ relocation_index_++;
+ relocation_group_index_++;
+
+ return &reloc_;
+ }
+ private:
+ bool read_group_fields() {
+ group_size_ = decoder_.pop_front();
+ group_flags_ = decoder_.pop_front();
+
+ if (is_relocation_grouped_by_offset_delta()) {
+ group_r_offset_delta_ = decoder_.pop_front();
+ }
+
+ if (is_relocation_grouped_by_info()) {
+ reloc_.r_info = decoder_.pop_front();
+ }
+
+ if (is_relocation_group_has_addend() &&
+ is_relocation_grouped_by_addend()) {
+#if !defined(USE_RELA)
+ // This platform does not support rela, and yet we have it encoded in android_rel section.
+ DL_ERR("unexpected r_addend in android.rel section");
+ return false;
+#else
+ reloc_.r_addend += decoder_.pop_front();
+ } else if (!is_relocation_group_has_addend()) {
+ reloc_.r_addend = 0;
+#endif
+ }
+
+ relocation_group_index_ = 0;
+ return true;
+ }
+
+ bool is_relocation_grouped_by_info() {
+ return (group_flags_ & RELOCATION_GROUPED_BY_INFO_FLAG) != 0;
+ }
+
+ bool is_relocation_grouped_by_offset_delta() {
+ return (group_flags_ & RELOCATION_GROUPED_BY_OFFSET_DELTA_FLAG) != 0;
+ }
+
+ bool is_relocation_grouped_by_addend() {
+ return (group_flags_ & RELOCATION_GROUPED_BY_ADDEND_FLAG) != 0;
+ }
+
+ bool is_relocation_group_has_addend() {
+ return (group_flags_ & RELOCATION_GROUP_HAS_ADDEND_FLAG) != 0;
+ }
+
+ decoder_t decoder_;
+ size_t relocation_count_;
+ size_t group_size_;
+ size_t group_flags_;
+ size_t group_r_offset_delta_;
+ size_t relocation_index_;
+ size_t relocation_group_index_;
+ rel_t reloc_;
+};
+
+#endif // __LINKER_RELOC_ITERATORS_H
diff --git a/linker/linker_relocs.h b/linker/linker_relocs.h
new file mode 100644
index 0000000..12c1497
--- /dev/null
+++ b/linker/linker_relocs.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LINKER_RELOCS_H
+#define __LINKER_RELOCS_H
+
+#include <elf.h>
+
+#define R_GENERIC_NONE 0 // R_*_NONE is always 0
+
+#if defined (__aarch64__)
+
+#define R_GENERIC_JUMP_SLOT R_AARCH64_JUMP_SLOT
+#define R_GENERIC_GLOB_DAT R_AARCH64_GLOB_DAT
+#define R_GENERIC_RELATIVE R_AARCH64_RELATIVE
+#define R_GENERIC_IRELATIVE R_AARCH64_IRELATIVE
+
+#elif defined (__arm__)
+
+#define R_GENERIC_JUMP_SLOT R_ARM_JUMP_SLOT
+#define R_GENERIC_GLOB_DAT R_ARM_GLOB_DAT
+#define R_GENERIC_RELATIVE R_ARM_RELATIVE
+#define R_GENERIC_IRELATIVE R_ARM_IRELATIVE
+
+#elif defined (__i386__)
+
+#define R_GENERIC_JUMP_SLOT R_386_JMP_SLOT
+#define R_GENERIC_GLOB_DAT R_386_GLOB_DAT
+#define R_GENERIC_RELATIVE R_386_RELATIVE
+#define R_GENERIC_IRELATIVE R_386_IRELATIVE
+
+#elif defined (__x86_64__)
+
+#define R_GENERIC_JUMP_SLOT R_X86_64_JUMP_SLOT
+#define R_GENERIC_GLOB_DAT R_X86_64_GLOB_DAT
+#define R_GENERIC_RELATIVE R_X86_64_RELATIVE
+#define R_GENERIC_IRELATIVE R_X86_64_IRELATIVE
+
+#endif
+
+#endif // __LINKER_RELOCS_H
diff --git a/linker/linker_sdk_versions.cpp b/linker/linker_sdk_versions.cpp
new file mode 100644
index 0000000..9aebb06
--- /dev/null
+++ b/linker/linker_sdk_versions.cpp
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker.h"
+#include <android/api-level.h>
+#include <atomic>
+
+static std::atomic<uint32_t> g_target_sdk_version(__ANDROID_API__);
+
+void set_application_target_sdk_version(uint32_t target) {
+ // translate current sdk_version to platform sdk_version
+ if (target == 0) {
+ target = __ANDROID_API__;
+ }
+ g_target_sdk_version = target;
+}
+
+uint32_t get_application_target_sdk_version() {
+ return g_target_sdk_version;
+}
+
diff --git a/linker/linker_sleb128.h b/linker/linker_sleb128.h
new file mode 100644
index 0000000..c4df259
--- /dev/null
+++ b/linker/linker_sleb128.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _LINKER_SLEB128_H
+#define _LINKER_SLEB128_H
+
+#include <stdint.h>
+
+#include "linker_debug.h"
+
+// Helper classes for decoding LEB128, used in packed relocation data.
+// http://en.wikipedia.org/wiki/LEB128
+
+class sleb128_decoder {
+ public:
+ sleb128_decoder(const uint8_t* buffer, size_t count)
+ : current_(buffer), end_(buffer+count) { }
+
+ size_t pop_front() {
+ size_t value = 0;
+ static const size_t size = CHAR_BIT * sizeof(value);
+
+ size_t shift = 0;
+ uint8_t byte;
+
+ do {
+ if (current_ >= end_) {
+ __libc_fatal("sleb128_decoder ran out of bounds");
+ }
+ byte = *current_++;
+ value |= (static_cast<size_t>(byte & 127) << shift);
+ shift += 7;
+ } while (byte & 128);
+
+ if (shift < size && (byte & 64)) {
+ value |= -(static_cast<size_t>(1) << shift);
+ }
+
+ return value;
+ }
+
+ private:
+ const uint8_t* current_;
+ const uint8_t* const end_;
+};
+
+#endif // __LINKER_SLEB128_H
diff --git a/linker/linker_soinfo.cpp b/linker/linker_soinfo.cpp
new file mode 100644
index 0000000..59bdc4d
--- /dev/null
+++ b/linker/linker_soinfo.cpp
@@ -0,0 +1,795 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "linker_soinfo.h"
+
+#include <dlfcn.h>
+#include <elf.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "linker_debug.h"
+#include "linker_globals.h"
+#include "linker_logger.h"
+#include "linker_utils.h"
+
+// TODO(dimitry): These functions are currently located in linker.cpp - find a better place for it
+bool find_verdef_version_index(const soinfo* si, const version_info* vi, ElfW(Versym)* versym);
+ElfW(Addr) call_ifunc_resolver(ElfW(Addr) resolver_addr);
+uint32_t get_application_target_sdk_version();
+
+soinfo::soinfo(android_namespace_t* ns, const char* realpath,
+ const struct stat* file_stat, off64_t file_offset,
+ int rtld_flags) {
+ memset(this, 0, sizeof(*this));
+
+ if (realpath != nullptr) {
+ realpath_ = realpath;
+ }
+
+ flags_ = FLAG_NEW_SOINFO;
+ version_ = SOINFO_VERSION;
+
+ if (file_stat != nullptr) {
+ this->st_dev_ = file_stat->st_dev;
+ this->st_ino_ = file_stat->st_ino;
+ this->file_offset_ = file_offset;
+ }
+
+ this->rtld_flags_ = rtld_flags;
+ this->primary_namespace_ = ns;
+}
+
+soinfo::~soinfo() {
+ g_soinfo_handles_map.erase(handle_);
+}
+
+void soinfo::set_dt_runpath(const char* path) {
+ if (!has_min_version(3)) {
+ return;
+ }
+
+ std::vector<std::string> runpaths;
+
+ split_path(path, ":", &runpaths);
+
+ std::string origin = dirname(get_realpath());
+ // FIXME: add $LIB and $PLATFORM.
+ std::pair<std::string, std::string> substs[] = {{"ORIGIN", origin}};
+ for (auto&& s : runpaths) {
+ size_t pos = 0;
+ while (pos < s.size()) {
+ pos = s.find("$", pos);
+ if (pos == std::string::npos) break;
+ for (const auto& subst : substs) {
+ const std::string& token = subst.first;
+ const std::string& replacement = subst.second;
+ if (s.substr(pos + 1, token.size()) == token) {
+ s.replace(pos, token.size() + 1, replacement);
+ // -1 to compensate for the ++pos below.
+ pos += replacement.size() - 1;
+ break;
+ } else if (s.substr(pos + 1, token.size() + 2) == "{" + token + "}") {
+ s.replace(pos, token.size() + 3, replacement);
+ pos += replacement.size() - 1;
+ break;
+ }
+ }
+ // Skip $ in case it did not match any of the known substitutions.
+ ++pos;
+ }
+ }
+
+ resolve_paths(runpaths, &dt_runpath_);
+}
+
+const ElfW(Versym)* soinfo::get_versym(size_t n) const {
+ if (has_min_version(2) && versym_ != nullptr) {
+ return versym_ + n;
+ }
+
+ return nullptr;
+}
+
+ElfW(Addr) soinfo::get_verneed_ptr() const {
+ if (has_min_version(2)) {
+ return verneed_ptr_;
+ }
+
+ return 0;
+}
+
+size_t soinfo::get_verneed_cnt() const {
+ if (has_min_version(2)) {
+ return verneed_cnt_;
+ }
+
+ return 0;
+}
+
+ElfW(Addr) soinfo::get_verdef_ptr() const {
+ if (has_min_version(2)) {
+ return verdef_ptr_;
+ }
+
+ return 0;
+}
+
+size_t soinfo::get_verdef_cnt() const {
+ if (has_min_version(2)) {
+ return verdef_cnt_;
+ }
+
+ return 0;
+}
+
+bool soinfo::find_symbol_by_name(SymbolName& symbol_name,
+ const version_info* vi,
+ const ElfW(Sym)** symbol) const {
+ uint32_t symbol_index;
+ bool success =
+ is_gnu_hash() ?
+ gnu_lookup(symbol_name, vi, &symbol_index) :
+ elf_lookup(symbol_name, vi, &symbol_index);
+
+ if (success) {
+ *symbol = symbol_index == 0 ? nullptr : symtab_ + symbol_index;
+ }
+
+ return success;
+}
+
+static bool is_symbol_global_and_defined(const soinfo* si, const ElfW(Sym)* s) {
+ if (ELF_ST_BIND(s->st_info) == STB_GLOBAL ||
+ ELF_ST_BIND(s->st_info) == STB_WEAK) {
+ return s->st_shndx != SHN_UNDEF;
+ } else if (ELF_ST_BIND(s->st_info) != STB_LOCAL) {
+ DL_WARN("unexpected ST_BIND value: %d for \"%s\" in \"%s\"",
+ ELF_ST_BIND(s->st_info), si->get_string(s->st_name), si->get_realpath());
+ }
+
+ return false;
+}
+
+static const ElfW(Versym) kVersymHiddenBit = 0x8000;
+
+static inline bool is_versym_hidden(const ElfW(Versym)* versym) {
+ // the symbol is hidden if bit 15 of versym is set.
+ return versym != nullptr && (*versym & kVersymHiddenBit) != 0;
+}
+
+static inline bool check_symbol_version(const ElfW(Versym) verneed,
+ const ElfW(Versym)* verdef) {
+ return verneed == kVersymNotNeeded ||
+ verdef == nullptr ||
+ verneed == (*verdef & ~kVersymHiddenBit);
+}
+
+bool soinfo::gnu_lookup(SymbolName& symbol_name,
+ const version_info* vi,
+ uint32_t* symbol_index) const {
+ uint32_t hash = symbol_name.gnu_hash();
+ uint32_t h2 = hash >> gnu_shift2_;
+
+ uint32_t bloom_mask_bits = sizeof(ElfW(Addr))*8;
+ uint32_t word_num = (hash / bloom_mask_bits) & gnu_maskwords_;
+ ElfW(Addr) bloom_word = gnu_bloom_filter_[word_num];
+
+ *symbol_index = 0;
+
+ TRACE_TYPE(LOOKUP, "SEARCH %s in %s@%p (gnu)",
+ symbol_name.get_name(), get_realpath(), reinterpret_cast<void*>(base));
+
+ // test against bloom filter
+ if ((1 & (bloom_word >> (hash % bloom_mask_bits)) & (bloom_word >> (h2 % bloom_mask_bits))) == 0) {
+ TRACE_TYPE(LOOKUP, "NOT FOUND %s in %s@%p",
+ symbol_name.get_name(), get_realpath(), reinterpret_cast<void*>(base));
+
+ return true;
+ }
+
+ // bloom test says "probably yes"...
+ uint32_t n = gnu_bucket_[hash % gnu_nbucket_];
+
+ if (n == 0) {
+ TRACE_TYPE(LOOKUP, "NOT FOUND %s in %s@%p",
+ symbol_name.get_name(), get_realpath(), reinterpret_cast<void*>(base));
+
+ return true;
+ }
+
+ // lookup versym for the version definition in this library
+ // note the difference between "version is not requested" (vi == nullptr)
+ // and "version not found". In the first case verneed is kVersymNotNeeded
+ // which implies that the default version can be accepted; the second case results in
+ // verneed = 1 (kVersymGlobal) and implies that we should ignore versioned symbols
+ // for this library and consider only *global* ones.
+ ElfW(Versym) verneed = 0;
+ if (!find_verdef_version_index(this, vi, &verneed)) {
+ return false;
+ }
+
+ do {
+ ElfW(Sym)* s = symtab_ + n;
+ const ElfW(Versym)* verdef = get_versym(n);
+ // skip hidden versions when verneed == kVersymNotNeeded (0)
+ if (verneed == kVersymNotNeeded && is_versym_hidden(verdef)) {
+ continue;
+ }
+ if (((gnu_chain_[n] ^ hash) >> 1) == 0 &&
+ check_symbol_version(verneed, verdef) &&
+ strcmp(get_string(s->st_name), symbol_name.get_name()) == 0 &&
+ is_symbol_global_and_defined(this, s)) {
+ TRACE_TYPE(LOOKUP, "FOUND %s in %s (%p) %zd",
+ symbol_name.get_name(), get_realpath(), reinterpret_cast<void*>(s->st_value),
+ static_cast<size_t>(s->st_size));
+ *symbol_index = n;
+ return true;
+ }
+ } while ((gnu_chain_[n++] & 1) == 0);
+
+ TRACE_TYPE(LOOKUP, "NOT FOUND %s in %s@%p",
+ symbol_name.get_name(), get_realpath(), reinterpret_cast<void*>(base));
+
+ return true;
+}
+
+bool soinfo::elf_lookup(SymbolName& symbol_name,
+ const version_info* vi,
+ uint32_t* symbol_index) const {
+ uint32_t hash = symbol_name.elf_hash();
+
+ TRACE_TYPE(LOOKUP, "SEARCH %s in %s@%p h=%x(elf) %zd",
+ symbol_name.get_name(), get_realpath(),
+ reinterpret_cast<void*>(base), hash, hash % nbucket_);
+
+ ElfW(Versym) verneed = 0;
+ if (!find_verdef_version_index(this, vi, &verneed)) {
+ return false;
+ }
+
+ for (uint32_t n = bucket_[hash % nbucket_]; n != 0; n = chain_[n]) {
+ ElfW(Sym)* s = symtab_ + n;
+ const ElfW(Versym)* verdef = get_versym(n);
+
+ // skip hidden versions when verneed == 0
+ if (verneed == kVersymNotNeeded && is_versym_hidden(verdef)) {
+ continue;
+ }
+
+ if (check_symbol_version(verneed, verdef) &&
+ strcmp(get_string(s->st_name), symbol_name.get_name()) == 0 &&
+ is_symbol_global_and_defined(this, s)) {
+ TRACE_TYPE(LOOKUP, "FOUND %s in %s (%p) %zd",
+ symbol_name.get_name(), get_realpath(),
+ reinterpret_cast<void*>(s->st_value),
+ static_cast<size_t>(s->st_size));
+ *symbol_index = n;
+ return true;
+ }
+ }
+
+ TRACE_TYPE(LOOKUP, "NOT FOUND %s in %s@%p %x %zd",
+ symbol_name.get_name(), get_realpath(),
+ reinterpret_cast<void*>(base), hash, hash % nbucket_);
+
+ *symbol_index = 0;
+ return true;
+}
+
+ElfW(Sym)* soinfo::find_symbol_by_address(const void* addr) {
+ return is_gnu_hash() ? gnu_addr_lookup(addr) : elf_addr_lookup(addr);
+}
+
+static bool symbol_matches_soaddr(const ElfW(Sym)* sym, ElfW(Addr) soaddr) {
+ return sym->st_shndx != SHN_UNDEF &&
+ soaddr >= sym->st_value &&
+ soaddr < sym->st_value + sym->st_size;
+}
+
+ElfW(Sym)* soinfo::gnu_addr_lookup(const void* addr) {
+ ElfW(Addr) soaddr = reinterpret_cast<ElfW(Addr)>(addr) - load_bias;
+
+ for (size_t i = 0; i < gnu_nbucket_; ++i) {
+ uint32_t n = gnu_bucket_[i];
+
+ if (n == 0) {
+ continue;
+ }
+
+ do {
+ ElfW(Sym)* sym = symtab_ + n;
+ if (symbol_matches_soaddr(sym, soaddr)) {
+ return sym;
+ }
+ } while ((gnu_chain_[n++] & 1) == 0);
+ }
+
+ return nullptr;
+}
+
+ElfW(Sym)* soinfo::elf_addr_lookup(const void* addr) {
+ ElfW(Addr) soaddr = reinterpret_cast<ElfW(Addr)>(addr) - load_bias;
+
+ // Search the library's symbol table for any defined symbol which
+ // contains this address.
+ for (size_t i = 0; i < nchain_; ++i) {
+ ElfW(Sym)* sym = symtab_ + i;
+ if (symbol_matches_soaddr(sym, soaddr)) {
+ return sym;
+ }
+ }
+
+ return nullptr;
+}
+
+static void call_function(const char* function_name __unused,
+ linker_ctor_function_t function,
+ const char* realpath __unused) {
+ if (function == nullptr || reinterpret_cast<uintptr_t>(function) == static_cast<uintptr_t>(-1)) {
+ return;
+ }
+
+ TRACE("[ Calling c-tor %s @ %p for '%s' ]", function_name, function, realpath);
+ function(g_argc, g_argv, g_envp);
+ TRACE("[ Done calling c-tor %s @ %p for '%s' ]", function_name, function, realpath);
+}
+
+static void call_function(const char* function_name __unused,
+ linker_dtor_function_t function,
+ const char* realpath __unused) {
+ if (function == nullptr || reinterpret_cast<uintptr_t>(function) == static_cast<uintptr_t>(-1)) {
+ return;
+ }
+
+ TRACE("[ Calling d-tor %s @ %p for '%s' ]", function_name, function, realpath);
+ function();
+ TRACE("[ Done calling d-tor %s @ %p for '%s' ]", function_name, function, realpath);
+}
+
+template <typename F>
+static void call_array(const char* array_name __unused,
+ F* functions,
+ size_t count,
+ bool reverse,
+ const char* realpath) {
+ if (functions == nullptr) {
+ return;
+ }
+
+ TRACE("[ Calling %s (size %zd) @ %p for '%s' ]", array_name, count, functions, realpath);
+
+ int begin = reverse ? (count - 1) : 0;
+ int end = reverse ? -1 : count;
+ int step = reverse ? -1 : 1;
+
+ for (int i = begin; i != end; i += step) {
+ TRACE("[ %s[%d] == %p ]", array_name, i, functions[i]);
+ call_function("function", functions[i], realpath);
+ }
+
+ TRACE("[ Done calling %s for '%s' ]", array_name, realpath);
+}
+
+void soinfo::call_pre_init_constructors() {
+ // DT_PREINIT_ARRAY functions are called before any other constructors for executables,
+ // but ignored in a shared library.
+ call_array("DT_PREINIT_ARRAY", preinit_array_, preinit_array_count_, false, get_realpath());
+}
+
+void soinfo::call_constructors() {
+ if (constructors_called) {
+ return;
+ }
+
+ // We set constructors_called before actually calling the constructors, otherwise it doesn't
+ // protect against recursive constructor calls. One simple example of constructor recursion
+ // is the libc debug malloc, which is implemented in libc_malloc_debug_leak.so:
+ // 1. The program depends on libc, so libc's constructor is called here.
+ // 2. The libc constructor calls dlopen() to load libc_malloc_debug_leak.so.
+ // 3. dlopen() calls the constructors on the newly created
+ // soinfo for libc_malloc_debug_leak.so.
+ // 4. The debug .so depends on libc, so CallConstructors is
+ // called again with the libc soinfo. If it doesn't trigger the early-
+ // out above, the libc constructor will be called again (recursively!).
+ constructors_called = true;
+
+ if (!is_main_executable() && preinit_array_ != nullptr) {
+ // The GNU dynamic linker silently ignores these, but we warn the developer.
+ PRINT("\"%s\": ignoring DT_PREINIT_ARRAY in shared library!", get_realpath());
+ }
+
+ get_children().for_each([] (soinfo* si) {
+ si->call_constructors();
+ });
+
+ TRACE("\"%s\": calling constructors", get_realpath());
+
+ // DT_INIT should be called before DT_INIT_ARRAY if both are present.
+ call_function("DT_INIT", init_func_, get_realpath());
+ call_array("DT_INIT_ARRAY", init_array_, init_array_count_, false, get_realpath());
+}
+
+void soinfo::call_destructors() {
+ if (!constructors_called) {
+ return;
+ }
+ TRACE("\"%s\": calling destructors", get_realpath());
+
+ // DT_FINI_ARRAY must be parsed in reverse order.
+ call_array("DT_FINI_ARRAY", fini_array_, fini_array_count_, true, get_realpath());
+
+ // DT_FINI should be called after DT_FINI_ARRAY if both are present.
+ call_function("DT_FINI", fini_func_, get_realpath());
+}
+
+void soinfo::add_child(soinfo* child) {
+ if (has_min_version(0)) {
+ child->parents_.push_back(this);
+ this->children_.push_back(child);
+ }
+}
+
+void soinfo::remove_all_links() {
+ if (!has_min_version(0)) {
+ return;
+ }
+
+ // 1. Untie connected soinfos from 'this'.
+ children_.for_each([&] (soinfo* child) {
+ child->parents_.remove_if([&] (const soinfo* parent) {
+ return parent == this;
+ });
+ });
+
+ parents_.for_each([&] (soinfo* parent) {
+ parent->children_.remove_if([&] (const soinfo* child) {
+ return child == this;
+ });
+ });
+
+ // 2. Remove from the primary namespace
+ primary_namespace_->remove_soinfo(this);
+ primary_namespace_ = nullptr;
+
+ // 3. Remove from secondary namespaces
+ secondary_namespaces_.for_each([&](android_namespace_t* ns) {
+ ns->remove_soinfo(this);
+ });
+
+
+ // 4. Once everything untied - clear local lists.
+ parents_.clear();
+ children_.clear();
+ secondary_namespaces_.clear();
+}
+
+dev_t soinfo::get_st_dev() const {
+ if (has_min_version(0)) {
+ return st_dev_;
+ }
+
+ return 0;
+};
+
+ino_t soinfo::get_st_ino() const {
+ if (has_min_version(0)) {
+ return st_ino_;
+ }
+
+ return 0;
+}
+
+off64_t soinfo::get_file_offset() const {
+ if (has_min_version(1)) {
+ return file_offset_;
+ }
+
+ return 0;
+}
+
+uint32_t soinfo::get_rtld_flags() const {
+ if (has_min_version(1)) {
+ return rtld_flags_;
+ }
+
+ return 0;
+}
+
+uint32_t soinfo::get_dt_flags_1() const {
+ if (has_min_version(1)) {
+ return dt_flags_1_;
+ }
+
+ return 0;
+}
+
+void soinfo::set_dt_flags_1(uint32_t dt_flags_1) {
+ if (has_min_version(1)) {
+ if ((dt_flags_1 & DF_1_GLOBAL) != 0) {
+ rtld_flags_ |= RTLD_GLOBAL;
+ }
+
+ if ((dt_flags_1 & DF_1_NODELETE) != 0) {
+ rtld_flags_ |= RTLD_NODELETE;
+ }
+
+ dt_flags_1_ = dt_flags_1;
+ }
+}
+
+void soinfo::set_nodelete() {
+ rtld_flags_ |= RTLD_NODELETE;
+}
+
+const char* soinfo::get_realpath() const {
+#if defined(__work_around_b_24465209__)
+ if (has_min_version(2)) {
+ return realpath_.c_str();
+ } else {
+ return old_name_;
+ }
+#else
+ return realpath_.c_str();
+#endif
+}
+
+void soinfo::set_soname(const char* soname) {
+#if defined(__work_around_b_24465209__)
+ if (has_min_version(2)) {
+ soname_ = soname;
+ }
+ strlcpy(old_name_, soname_, sizeof(old_name_));
+#else
+ soname_ = soname;
+#endif
+}
+
+const char* soinfo::get_soname() const {
+#if defined(__work_around_b_24465209__)
+ if (has_min_version(2)) {
+ return soname_;
+ } else {
+ return old_name_;
+ }
+#else
+ return soname_;
+#endif
+}
+
+// This is a return on get_children()/get_parents() if
+// 'this->flags' does not have FLAG_NEW_SOINFO set.
+static soinfo_list_t g_empty_list;
+
+soinfo_list_t& soinfo::get_children() {
+ if (has_min_version(0)) {
+ return children_;
+ }
+
+ return g_empty_list;
+}
+
+const soinfo_list_t& soinfo::get_children() const {
+ if (has_min_version(0)) {
+ return children_;
+ }
+
+ return g_empty_list;
+}
+
+soinfo_list_t& soinfo::get_parents() {
+ if (has_min_version(0)) {
+ return parents_;
+ }
+
+ return g_empty_list;
+}
+
+static std::vector<std::string> g_empty_runpath;
+
+const std::vector<std::string>& soinfo::get_dt_runpath() const {
+ if (has_min_version(3)) {
+ return dt_runpath_;
+ }
+
+ return g_empty_runpath;
+}
+
+android_namespace_t* soinfo::get_primary_namespace() {
+ if (has_min_version(3)) {
+ return primary_namespace_;
+ }
+
+ return &g_default_namespace;
+}
+
+void soinfo::add_secondary_namespace(android_namespace_t* secondary_ns) {
+ CHECK(has_min_version(3));
+ secondary_namespaces_.push_back(secondary_ns);
+}
+
+ElfW(Addr) soinfo::resolve_symbol_address(const ElfW(Sym)* s) const {
+ if (ELF_ST_TYPE(s->st_info) == STT_GNU_IFUNC) {
+ return call_ifunc_resolver(s->st_value + load_bias);
+ }
+
+ return static_cast<ElfW(Addr)>(s->st_value + load_bias);
+}
+
+const char* soinfo::get_string(ElfW(Word) index) const {
+ if (has_min_version(1) && (index >= strtab_size_)) {
+ __libc_fatal("%s: strtab out of bounds error; STRSZ=%zd, name=%d",
+ get_realpath(), strtab_size_, index);
+ }
+
+ return strtab_ + index;
+}
+
+bool soinfo::is_gnu_hash() const {
+ return (flags_ & FLAG_GNU_HASH) != 0;
+}
+
+bool soinfo::can_unload() const {
+ return !is_linked() || ((get_rtld_flags() & (RTLD_NODELETE | RTLD_GLOBAL)) == 0);
+}
+
+bool soinfo::is_linked() const {
+ return (flags_ & FLAG_LINKED) != 0;
+}
+
+bool soinfo::is_main_executable() const {
+ return (flags_ & FLAG_EXE) != 0;
+}
+
+bool soinfo::is_linker() const {
+ return (flags_ & FLAG_LINKER) != 0;
+}
+
+void soinfo::set_linked() {
+ flags_ |= FLAG_LINKED;
+}
+
+void soinfo::set_linker_flag() {
+ flags_ |= FLAG_LINKER;
+}
+
+void soinfo::set_main_executable() {
+ flags_ |= FLAG_EXE;
+}
+
+void soinfo::increment_ref_count() {
+ local_group_root_->ref_count_++;
+}
+
+size_t soinfo::decrement_ref_count() {
+ return --local_group_root_->ref_count_;
+}
+
+soinfo* soinfo::get_local_group_root() const {
+ return local_group_root_;
+}
+
+
+void soinfo::set_mapped_by_caller(bool mapped_by_caller) {
+ if (mapped_by_caller) {
+ flags_ |= FLAG_MAPPED_BY_CALLER;
+ } else {
+ flags_ &= ~FLAG_MAPPED_BY_CALLER;
+ }
+}
+
+bool soinfo::is_mapped_by_caller() const {
+ return (flags_ & FLAG_MAPPED_BY_CALLER) != 0;
+}
+
+// This function returns api-level at the time of
+// dlopen/load. Note that libraries opened by system
+// will always have 'current' api level.
+uint32_t soinfo::get_target_sdk_version() const {
+ if (!has_min_version(2)) {
+ return __ANDROID_API__;
+ }
+
+ return local_group_root_->target_sdk_version_;
+}
+
+uintptr_t soinfo::get_handle() const {
+ CHECK(has_min_version(3));
+ CHECK(handle_ != 0);
+ return handle_;
+}
+
+void* soinfo::to_handle() {
+ if (get_application_target_sdk_version() <= 23 || !has_min_version(3)) {
+ return this;
+ }
+
+ return reinterpret_cast<void*>(get_handle());
+}
+
+void soinfo::generate_handle() {
+ CHECK(has_min_version(3));
+ CHECK(handle_ == 0); // Make sure this is the first call
+
+ // Make sure the handle is unique and does not collide
+ // with special values which are RTLD_DEFAULT and RTLD_NEXT.
+ do {
+ arc4random_buf(&handle_, sizeof(handle_));
+ // the least significant bit for the handle is always 1
+ // making it easy to test the type of handle passed to
+ // dl* functions.
+ handle_ = handle_ | 1;
+ } while (handle_ == reinterpret_cast<uintptr_t>(RTLD_DEFAULT) ||
+ handle_ == reinterpret_cast<uintptr_t>(RTLD_NEXT) ||
+ g_soinfo_handles_map.find(handle_) != g_soinfo_handles_map.end());
+
+ g_soinfo_handles_map[handle_] = this;
+}
+
+// TODO(dimitry): Move SymbolName methods to a separate file.
+
+uint32_t calculate_elf_hash(const char* name) {
+ const uint8_t* name_bytes = reinterpret_cast<const uint8_t*>(name);
+ uint32_t h = 0, g;
+
+ while (*name_bytes) {
+ h = (h << 4) + *name_bytes++;
+ g = h & 0xf0000000;
+ h ^= g;
+ h ^= g >> 24;
+ }
+
+ return h;
+}
+
+uint32_t SymbolName::elf_hash() {
+ if (!has_elf_hash_) {
+ elf_hash_ = calculate_elf_hash(name_);
+ has_elf_hash_ = true;
+ }
+
+ return elf_hash_;
+}
+
+uint32_t SymbolName::gnu_hash() {
+ if (!has_gnu_hash_) {
+ uint32_t h = 5381;
+ const uint8_t* name = reinterpret_cast<const uint8_t*>(name_);
+ while (*name != 0) {
+ h += (h << 5) + *name++; // h*33 + c = h + h * 32 + c = h + h << 5 + c
+ }
+
+ gnu_hash_ = h;
+ has_gnu_hash_ = true;
+ }
+
+ return gnu_hash_;
+}
+
+
diff --git a/linker/linker_soinfo.h b/linker/linker_soinfo.h
new file mode 100644
index 0000000..d7b584e
--- /dev/null
+++ b/linker/linker_soinfo.h
@@ -0,0 +1,345 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef __LINKER_SOINFO_H
+#define __LINKER_SOINFO_H
+
+#include <link.h>
+
+#include <string>
+
+#include "linker_namespaces.h"
+
+#define FLAG_LINKED 0x00000001
+#define FLAG_EXE 0x00000004 // The main executable
+#define FLAG_LINKER 0x00000010 // The linker itself
+#define FLAG_GNU_HASH 0x00000040 // uses gnu hash
+#define FLAG_MAPPED_BY_CALLER 0x00000080 // the map is reserved by the caller
+ // and should not be unmapped
+#define FLAG_NEW_SOINFO 0x40000000 // new soinfo format
+
+#define SOINFO_VERSION 3
+
+typedef void (*linker_dtor_function_t)();
+typedef void (*linker_ctor_function_t)(int, char**, char**);
+
+class SymbolName {
+ public:
+ explicit SymbolName(const char* name)
+ : name_(name), has_elf_hash_(false), has_gnu_hash_(false),
+ elf_hash_(0), gnu_hash_(0) { }
+
+ const char* get_name() {
+ return name_;
+ }
+
+ uint32_t elf_hash();
+ uint32_t gnu_hash();
+
+ private:
+ const char* name_;
+ bool has_elf_hash_;
+ bool has_gnu_hash_;
+ uint32_t elf_hash_;
+ uint32_t gnu_hash_;
+
+ DISALLOW_IMPLICIT_CONSTRUCTORS(SymbolName);
+};
+
+struct version_info {
+ constexpr version_info() : elf_hash(0), name(nullptr), target_si(nullptr) {}
+
+ uint32_t elf_hash;
+ const char* name;
+ const soinfo* target_si;
+};
+
+// TODO(dimitry): remove reference from soinfo member functions to this class.
+class VersionTracker;
+
+#if defined(__work_around_b_24465209__)
+#define SOINFO_NAME_LEN 128
+#endif
+
+struct soinfo {
+#if defined(__work_around_b_24465209__)
+ private:
+ char old_name_[SOINFO_NAME_LEN];
+#endif
+ public:
+ const ElfW(Phdr)* phdr;
+ size_t phnum;
+#if defined(__work_around_b_24465209__)
+ ElfW(Addr) unused0; // DO NOT USE, maintained for compatibility.
+#endif
+ ElfW(Addr) base;
+ size_t size;
+
+#if defined(__work_around_b_24465209__)
+ uint32_t unused1; // DO NOT USE, maintained for compatibility.
+#endif
+
+ ElfW(Dyn)* dynamic;
+
+#if defined(__work_around_b_24465209__)
+ uint32_t unused2; // DO NOT USE, maintained for compatibility
+ uint32_t unused3; // DO NOT USE, maintained for compatibility
+#endif
+
+ soinfo* next;
+ private:
+ uint32_t flags_;
+
+ const char* strtab_;
+ ElfW(Sym)* symtab_;
+
+ size_t nbucket_;
+ size_t nchain_;
+ uint32_t* bucket_;
+ uint32_t* chain_;
+
+#if defined(__mips__) || !defined(__LP64__)
+ // This is only used by mips and mips64, but needs to be here for
+ // all 32-bit architectures to preserve binary compatibility.
+ ElfW(Addr)** plt_got_;
+#endif
+
+#if defined(USE_RELA)
+ ElfW(Rela)* plt_rela_;
+ size_t plt_rela_count_;
+
+ ElfW(Rela)* rela_;
+ size_t rela_count_;
+#else
+ ElfW(Rel)* plt_rel_;
+ size_t plt_rel_count_;
+
+ ElfW(Rel)* rel_;
+ size_t rel_count_;
+#endif
+
+ linker_ctor_function_t* preinit_array_;
+ size_t preinit_array_count_;
+
+ linker_ctor_function_t* init_array_;
+ size_t init_array_count_;
+ linker_dtor_function_t* fini_array_;
+ size_t fini_array_count_;
+
+ linker_ctor_function_t init_func_;
+ linker_dtor_function_t fini_func_;
+
+#if defined(__arm__)
+ public:
+ // ARM EABI section used for stack unwinding.
+ uint32_t* ARM_exidx;
+ size_t ARM_exidx_count;
+ private:
+#elif defined(__mips__)
+ uint32_t mips_symtabno_;
+ uint32_t mips_local_gotno_;
+ uint32_t mips_gotsym_;
+ bool mips_relocate_got(const VersionTracker& version_tracker,
+ const soinfo_list_t& global_group,
+ const soinfo_list_t& local_group);
+#if !defined(__LP64__)
+ bool mips_check_and_adjust_fp_modes();
+#endif
+#endif
+ size_t ref_count_;
+ public:
+ link_map link_map_head;
+
+ bool constructors_called;
+
+ // When you read a virtual address from the ELF file, add this
+ // value to get the corresponding address in the process' address space.
+ ElfW(Addr) load_bias;
+
+#if !defined(__LP64__)
+ bool has_text_relocations;
+#endif
+ bool has_DT_SYMBOLIC;
+
+ public:
+ soinfo(android_namespace_t* ns, const char* name, const struct stat* file_stat,
+ off64_t file_offset, int rtld_flags);
+ ~soinfo();
+
+ void call_constructors();
+ void call_destructors();
+ void call_pre_init_constructors();
+ bool prelink_image();
+ bool link_image(const soinfo_list_t& global_group, const soinfo_list_t& local_group,
+ const android_dlextinfo* extinfo);
+ bool protect_relro();
+
+ void add_child(soinfo* child);
+ void remove_all_links();
+
+ ino_t get_st_ino() const;
+ dev_t get_st_dev() const;
+ off64_t get_file_offset() const;
+
+ uint32_t get_rtld_flags() const;
+ uint32_t get_dt_flags_1() const;
+ void set_dt_flags_1(uint32_t dt_flags_1);
+
+ soinfo_list_t& get_children();
+ const soinfo_list_t& get_children() const;
+
+ soinfo_list_t& get_parents();
+
+ bool find_symbol_by_name(SymbolName& symbol_name,
+ const version_info* vi,
+ const ElfW(Sym)** symbol) const;
+
+ ElfW(Sym)* find_symbol_by_address(const void* addr);
+ ElfW(Addr) resolve_symbol_address(const ElfW(Sym)* s) const;
+
+ const char* get_string(ElfW(Word) index) const;
+ bool can_unload() const;
+ bool is_gnu_hash() const;
+
+ bool inline has_min_version(uint32_t min_version __unused) const {
+#if defined(__work_around_b_24465209__)
+ return (flags_ & FLAG_NEW_SOINFO) != 0 && version_ >= min_version;
+#else
+ return true;
+#endif
+ }
+
+ bool is_linked() const;
+ bool is_linker() const;
+ bool is_main_executable() const;
+
+ void set_linked();
+ void set_linker_flag();
+ void set_main_executable();
+ void set_nodelete();
+
+ void increment_ref_count();
+ size_t decrement_ref_count();
+
+ soinfo* get_local_group_root() const;
+
+ void set_soname(const char* soname);
+ const char* get_soname() const;
+ const char* get_realpath() const;
+ const ElfW(Versym)* get_versym(size_t n) const;
+ ElfW(Addr) get_verneed_ptr() const;
+ size_t get_verneed_cnt() const;
+ ElfW(Addr) get_verdef_ptr() const;
+ size_t get_verdef_cnt() const;
+
+ uint32_t get_target_sdk_version() const;
+
+ void set_dt_runpath(const char *);
+ const std::vector<std::string>& get_dt_runpath() const;
+ android_namespace_t* get_primary_namespace();
+ void add_secondary_namespace(android_namespace_t* secondary_ns);
+
+ void set_mapped_by_caller(bool reserved_map);
+ bool is_mapped_by_caller() const;
+
+ uintptr_t get_handle() const;
+ void generate_handle();
+ void* to_handle();
+
+ private:
+ bool elf_lookup(SymbolName& symbol_name, const version_info* vi, uint32_t* symbol_index) const;
+ ElfW(Sym)* elf_addr_lookup(const void* addr);
+ bool gnu_lookup(SymbolName& symbol_name, const version_info* vi, uint32_t* symbol_index) const;
+ ElfW(Sym)* gnu_addr_lookup(const void* addr);
+
+ bool lookup_version_info(const VersionTracker& version_tracker, ElfW(Word) sym,
+ const char* sym_name, const version_info** vi);
+
+ template<typename ElfRelIteratorT>
+ bool relocate(const VersionTracker& version_tracker, ElfRelIteratorT&& rel_iterator,
+ const soinfo_list_t& global_group, const soinfo_list_t& local_group);
+
+ private:
+ // This part of the structure is only available
+ // when FLAG_NEW_SOINFO is set in this->flags.
+ uint32_t version_;
+
+ // version >= 0
+ dev_t st_dev_;
+ ino_t st_ino_;
+
+ // dependency graph
+ soinfo_list_t children_;
+ soinfo_list_t parents_;
+
+ // version >= 1
+ off64_t file_offset_;
+ uint32_t rtld_flags_;
+ uint32_t dt_flags_1_;
+ size_t strtab_size_;
+
+ // version >= 2
+
+ size_t gnu_nbucket_;
+ uint32_t* gnu_bucket_;
+ uint32_t* gnu_chain_;
+ uint32_t gnu_maskwords_;
+ uint32_t gnu_shift2_;
+ ElfW(Addr)* gnu_bloom_filter_;
+
+ soinfo* local_group_root_;
+
+ uint8_t* android_relocs_;
+ size_t android_relocs_size_;
+
+ const char* soname_;
+ std::string realpath_;
+
+ const ElfW(Versym)* versym_;
+
+ ElfW(Addr) verdef_ptr_;
+ size_t verdef_cnt_;
+
+ ElfW(Addr) verneed_ptr_;
+ size_t verneed_cnt_;
+
+ uint32_t target_sdk_version_;
+
+ // version >= 3
+ std::vector<std::string> dt_runpath_;
+ android_namespace_t* primary_namespace_;
+ android_namespace_list_t secondary_namespaces_;
+ uintptr_t handle_;
+
+ friend soinfo* get_libdl_info();
+};
+
+// This function is used by dlvsym() to calculate hash of sym_ver
+uint32_t calculate_elf_hash(const char* name);
+
+#endif /* __LINKER_SOINFO_H */
diff --git a/linker/linker_utils.cpp b/linker/linker_utils.cpp
new file mode 100644
index 0000000..e7447e4
--- /dev/null
+++ b/linker/linker_utils.cpp
@@ -0,0 +1,204 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker_utils.h"
+
+#include "linker_debug.h"
+#include "linker_globals.h"
+
+#include "android-base/strings.h"
+
+#include <sys/stat.h>
+#include <unistd.h>
+
+std::string dirname(const char* path) {
+ const char* last_slash = strrchr(path, '/');
+
+ if (last_slash == path) {
+ return "/";
+ } else if (last_slash == nullptr) {
+ return ".";
+ } else {
+ return std::string(path, last_slash - path);
+ }
+}
+
+bool normalize_path(const char* path, std::string* normalized_path) {
+ // Input should be an absolute path
+ if (path[0] != '/') {
+ PRINT("normalize_path - invalid input: \"%s\", the input path should be absolute", path);
+ return false;
+ }
+
+ const size_t len = strlen(path) + 1;
+ char buf[len];
+
+ const char* in_ptr = path;
+ char* out_ptr = buf;
+
+ while (*in_ptr != 0) {
+ if (*in_ptr == '/') {
+ char c1 = in_ptr[1];
+ if (c1 == '.') {
+ char c2 = in_ptr[2];
+ if (c2 == '/') {
+ in_ptr += 2;
+ continue;
+ } else if (c2 == '.' && (in_ptr[3] == '/' || in_ptr[3] == 0)) {
+ in_ptr += 3;
+ while (out_ptr > buf && *--out_ptr != '/') {
+ }
+ if (in_ptr[0] == 0) {
+ // retain '/'
+ out_ptr++;
+ }
+ continue;
+ }
+ } else if (c1 == '/') {
+ ++in_ptr;
+ continue;
+ }
+ }
+ *out_ptr++ = *in_ptr++;
+ }
+
+ *out_ptr = 0;
+ *normalized_path = buf;
+ return true;
+}
+
+bool file_is_in_dir(const std::string& file, const std::string& dir) {
+ const char* needle = dir.c_str();
+ const char* haystack = file.c_str();
+ size_t needle_len = strlen(needle);
+
+ return strncmp(haystack, needle, needle_len) == 0 &&
+ haystack[needle_len] == '/' &&
+ strchr(haystack + needle_len + 1, '/') == nullptr;
+}
+
+bool file_is_under_dir(const std::string& file, const std::string& dir) {
+ const char* needle = dir.c_str();
+ const char* haystack = file.c_str();
+ size_t needle_len = strlen(needle);
+
+ return strncmp(haystack, needle, needle_len) == 0 &&
+ haystack[needle_len] == '/';
+}
+
+const char* const kZipFileSeparator = "!/";
+
+bool parse_zip_path(const char* input_path, std::string* zip_path, std::string* entry_path) {
+ std::string normalized_path;
+ if (!normalize_path(input_path, &normalized_path)) {
+ return false;
+ }
+
+ const char* const path = normalized_path.c_str();
+ TRACE("Trying zip file open from path \"%s\" -> normalized \"%s\"", input_path, path);
+
+ // Treat an '!/' separator inside a path as the separator between the name
+ // of the zip file on disk and the subdirectory to search within it.
+ // For example, if path is "foo.zip!/bar/bas/x.so", then we search for
+ // "bar/bas/x.so" within "foo.zip".
+ const char* const separator = strstr(path, kZipFileSeparator);
+ if (separator == nullptr) {
+ return false;
+ }
+
+ char buf[512];
+ if (strlcpy(buf, path, sizeof(buf)) >= sizeof(buf)) {
+ PRINT("Warning: ignoring very long library path: %s", path);
+ return false;
+ }
+
+ buf[separator - path] = '\0';
+
+ *zip_path = buf;
+ *entry_path = &buf[separator - path + 2];
+
+ return true;
+}
+
+constexpr off64_t kPageMask = ~static_cast<off64_t>(PAGE_SIZE-1);
+
+off64_t page_start(off64_t offset) {
+ return offset & kPageMask;
+}
+
+bool safe_add(off64_t* out, off64_t a, size_t b) {
+ CHECK(a >= 0);
+ if (static_cast<uint64_t>(INT64_MAX - a) < b) {
+ return false;
+ }
+
+ *out = a + b;
+ return true;
+}
+
+size_t page_offset(off64_t offset) {
+ return static_cast<size_t>(offset & (PAGE_SIZE-1));
+}
+
+void split_path(const char* path, const char* delimiters,
+ std::vector<std::string>* paths) {
+ if (path != nullptr && path[0] != 0) {
+ *paths = android::base::Split(path, delimiters);
+ }
+}
+
+void resolve_paths(std::vector<std::string>& paths,
+ std::vector<std::string>* resolved_paths) {
+ resolved_paths->clear();
+ for (const auto& path : paths) {
+ char resolved_path[PATH_MAX];
+ const char* original_path = path.c_str();
+ if (realpath(original_path, resolved_path) != nullptr) {
+ struct stat s;
+ if (stat(resolved_path, &s) == 0) {
+ if (S_ISDIR(s.st_mode)) {
+ resolved_paths->push_back(resolved_path);
+ } else {
+ DL_WARN("Warning: \"%s\" is not a directory (excluding from path)", resolved_path);
+ continue;
+ }
+ } else {
+ DL_WARN("Warning: cannot stat file \"%s\": %s", resolved_path, strerror(errno));
+ continue;
+ }
+ } else {
+ std::string zip_path;
+ std::string entry_path;
+
+ std::string normalized_path;
+
+ if (!normalize_path(original_path, &normalized_path)) {
+ DL_WARN("Warning: unable to normalize \"%s\"", original_path);
+ continue;
+ }
+
+ if (parse_zip_path(normalized_path.c_str(), &zip_path, &entry_path)) {
+ if (realpath(zip_path.c_str(), resolved_path) == nullptr) {
+ DL_WARN("Warning: unable to resolve \"%s\": %s", zip_path.c_str(), strerror(errno));
+ continue;
+ }
+
+ resolved_paths->push_back(std::string(resolved_path) + kZipFileSeparator + entry_path);
+ }
+ }
+ }
+}
+
diff --git a/linker/linker_utils.h b/linker/linker_utils.h
new file mode 100644
index 0000000..2e015a5
--- /dev/null
+++ b/linker/linker_utils.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef __LINKER_UTILS_H
+#define __LINKER_UTILS_H
+
+#include <string>
+#include <vector>
+
+extern const char* const kZipFileSeparator;
+
+bool file_is_in_dir(const std::string& file, const std::string& dir);
+bool file_is_under_dir(const std::string& file, const std::string& dir);
+bool normalize_path(const char* path, std::string* normalized_path);
+bool parse_zip_path(const char* input_path, std::string* zip_path, std::string* entry_path);
+
+// For every path element this function checks of it exists, and is a directory,
+// and normalizes it:
+// 1. For regular path it converts it to realpath()
+// 2. For path in a zip file it uses realpath on the zipfile
+// normalizes entry name by calling normalize_path function.
+void resolve_paths(std::vector<std::string>& paths, std::vector<std::string>* resolved_paths);
+void split_path(const char* path, const char* delimiters, std::vector<std::string>* paths);
+
+std::string dirname(const char* path);
+
+off64_t page_start(off64_t offset);
+size_t page_offset(off64_t offset);
+bool safe_add(off64_t* out, off64_t a, size_t b);
+
+#endif
diff --git a/linker/rt.cpp b/linker/rt.cpp
new file mode 100644
index 0000000..710892a
--- /dev/null
+++ b/linker/rt.cpp
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * This function is an empty stub where GDB locates a breakpoint to get notified
+ * about linker activity. It canʼt be inlined away, can't be hidden.
+ */
+extern "C" void __attribute__((noinline)) __attribute__((visibility("default"))) rtld_db_dlactivity() {
+}
+
diff --git a/linker/tests/Android.mk b/linker/tests/Android.mk
new file mode 100644
index 0000000..d5b57f1
--- /dev/null
+++ b/linker/tests/Android.mk
@@ -0,0 +1,45 @@
+#
+# Copyright (C) 2012 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+LOCAL_PATH:= $(call my-dir)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := linker-unit-tests
+LOCAL_MODULE_STEM_32 := $(LOCAL_MODULE)32
+LOCAL_MODULE_STEM_64 := $(LOCAL_MODULE)64
+
+LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
+
+LOCAL_CFLAGS += -g -Wall -Wextra -Wunused -Werror
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/../../libc/
+
+LOCAL_SRC_FILES := \
+ linker_block_allocator_test.cpp \
+ linker_globals.cpp \
+ linked_list_test.cpp \
+ linker_memory_allocator_test.cpp \
+ linker_sleb128_test.cpp \
+ linker_utils_test.cpp \
+ ../linker_allocator.cpp \
+ ../linker_block_allocator.cpp \
+ ../linker_utils.cpp
+
+# for __libc_fatal
+LOCAL_SRC_FILES += ../../libc/bionic/libc_logging.cpp
+
+LOCAL_STATIC_LIBRARIES += libbase
+
+include $(BUILD_NATIVE_TEST)
diff --git a/linker/tests/linked_list_test.cpp b/linker/tests/linked_list_test.cpp
new file mode 100644
index 0000000..12348d9
--- /dev/null
+++ b/linker/tests/linked_list_test.cpp
@@ -0,0 +1,233 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdlib.h>
+#include <string>
+#include <sstream>
+
+#include <gtest/gtest.h>
+
+#include "../linked_list.h"
+
+namespace {
+
+bool alloc_called = false;
+bool free_called = false;
+
+class LinkedListTestAllocator {
+ public:
+ typedef LinkedListEntry<const char> entry_t;
+
+ static entry_t* alloc() {
+ alloc_called = true;
+ return reinterpret_cast<entry_t*>(::malloc(sizeof(entry_t)));
+ }
+
+ static void free(entry_t* p) {
+ free_called = true;
+ ::free(p);
+ }
+ private:
+ DISALLOW_IMPLICIT_CONSTRUCTORS(LinkedListTestAllocator);
+};
+
+typedef LinkedList<const char, LinkedListTestAllocator> test_list_t;
+
+std::string test_list_to_string(test_list_t& list) {
+ std::stringstream ss;
+ list.for_each([&] (const char* c) {
+ ss << c;
+ });
+
+ return ss.str();
+}
+
+};
+
+TEST(linked_list, simple) {
+ alloc_called = free_called = false;
+ test_list_t list;
+ ASSERT_EQ("", test_list_to_string(list));
+ ASSERT_TRUE(!alloc_called);
+ ASSERT_TRUE(!free_called);
+ list.push_front("a");
+ ASSERT_TRUE(alloc_called);
+ ASSERT_TRUE(!free_called);
+ ASSERT_EQ("a", test_list_to_string(list));
+ list.push_front("b");
+ ASSERT_EQ("ba", test_list_to_string(list));
+ list.push_front("c");
+ list.push_front("d");
+ ASSERT_EQ("dcba", test_list_to_string(list));
+ ASSERT_TRUE(alloc_called);
+ ASSERT_TRUE(!free_called);
+ alloc_called = free_called = false;
+ list.remove_if([] (const char* c) {
+ return *c == 'c';
+ });
+
+ ASSERT_TRUE(!alloc_called);
+ ASSERT_TRUE(free_called);
+
+ ASSERT_EQ("dba", test_list_to_string(list));
+ alloc_called = free_called = false;
+ list.remove_if([] (const char* c) {
+ return *c == '2';
+ });
+ ASSERT_TRUE(!alloc_called);
+ ASSERT_TRUE(!free_called);
+ ASSERT_EQ("dba", test_list_to_string(list));
+ list.clear();
+ ASSERT_TRUE(!alloc_called);
+ ASSERT_TRUE(free_called);
+ ASSERT_EQ("", test_list_to_string(list));
+}
+
+TEST(linked_list, push_pop) {
+ test_list_t list;
+ list.push_front("b");
+ list.push_front("a");
+ ASSERT_EQ("ab", test_list_to_string(list));
+ list.push_back("c");
+ ASSERT_EQ("abc", test_list_to_string(list));
+ ASSERT_STREQ("a", list.pop_front());
+ ASSERT_EQ("bc", test_list_to_string(list));
+ ASSERT_STREQ("b", list.pop_front());
+ ASSERT_EQ("c", test_list_to_string(list));
+ ASSERT_STREQ("c", list.pop_front());
+ ASSERT_EQ("", test_list_to_string(list));
+ ASSERT_TRUE(list.pop_front() == nullptr);
+ list.push_back("r");
+ ASSERT_EQ("r", test_list_to_string(list));
+ ASSERT_STREQ("r", list.pop_front());
+ ASSERT_TRUE(list.pop_front() == nullptr);
+}
+
+TEST(linked_list, remove_if_then_pop) {
+ test_list_t list;
+ list.push_back("a");
+ list.push_back("b");
+ list.push_back("c");
+ list.push_back("d");
+ list.remove_if([](const char* c) {
+ return *c == 'b' || *c == 'c';
+ });
+
+ ASSERT_EQ("ad", test_list_to_string(list));
+ ASSERT_STREQ("a", list.pop_front());
+ ASSERT_EQ("d", test_list_to_string(list));
+ ASSERT_STREQ("d", list.pop_front());
+ ASSERT_TRUE(list.pop_front() == nullptr);
+}
+
+TEST(linked_list, remove_if_last_then_push_back) {
+ test_list_t list;
+
+ list.push_back("a");
+ list.push_back("b");
+ list.push_back("c");
+ list.push_back("d");
+
+ list.remove_if([](const char* c) {
+ return *c == 'c' || *c == 'd';
+ });
+
+ ASSERT_EQ("ab", test_list_to_string(list));
+ list.push_back("d");
+ ASSERT_EQ("abd", test_list_to_string(list));
+}
+
+TEST(linked_list, copy_to_array) {
+ test_list_t list;
+ const size_t max_size = 128;
+ const char* buf[max_size];
+ memset(buf, 0, sizeof(buf));
+
+ ASSERT_EQ(0U, list.copy_to_array(buf, max_size));
+ ASSERT_EQ(nullptr, buf[0]);
+
+ list.push_back("a");
+ list.push_back("b");
+ list.push_back("c");
+ list.push_back("d");
+
+ memset(buf, 0, sizeof(buf));
+ ASSERT_EQ(2U, list.copy_to_array(buf, 2));
+ ASSERT_STREQ("a", buf[0]);
+ ASSERT_STREQ("b", buf[1]);
+ ASSERT_EQ(nullptr, buf[2]);
+
+ ASSERT_EQ(4U, list.copy_to_array(buf, max_size));
+ ASSERT_STREQ("a", buf[0]);
+ ASSERT_STREQ("b", buf[1]);
+ ASSERT_STREQ("c", buf[2]);
+ ASSERT_STREQ("d", buf[3]);
+ ASSERT_EQ(nullptr, buf[4]);
+
+ memset(buf, 0, sizeof(buf));
+ list.remove_if([](const char* c) {
+ return *c != 'c';
+ });
+ ASSERT_EQ(1U, list.copy_to_array(buf, max_size));
+ ASSERT_STREQ("c", buf[0]);
+ ASSERT_EQ(nullptr, buf[1]);
+
+ memset(buf, 0, sizeof(buf));
+
+ list.remove_if([](const char* c) {
+ return *c == 'c';
+ });
+
+ ASSERT_EQ(0U, list.copy_to_array(buf, max_size));
+ ASSERT_EQ(nullptr, buf[0]);
+}
+
+TEST(linked_list, test_visit) {
+ test_list_t list;
+ list.push_back("a");
+ list.push_back("b");
+ list.push_back("c");
+ list.push_back("d");
+
+ int visits = 0;
+ std::stringstream ss;
+ bool result = list.visit([&](const char* c) {
+ ++visits;
+ ss << c;
+ return true;
+ });
+
+ ASSERT_TRUE(result);
+ ASSERT_EQ(4, visits);
+ ASSERT_EQ("abcd", ss.str());
+
+ visits = 0;
+ ss.str(std::string());
+
+ result = list.visit([&](const char* c) {
+ if (++visits == 3) {
+ return false;
+ }
+
+ ss << c;
+ return true;
+ });
+
+ ASSERT_TRUE(!result);
+ ASSERT_EQ(3, visits);
+ ASSERT_EQ("ab", ss.str());
+}
+
diff --git a/linker/tests/linker_block_allocator_test.cpp b/linker/tests/linker_block_allocator_test.cpp
new file mode 100644
index 0000000..5adc425
--- /dev/null
+++ b/linker/tests/linker_block_allocator_test.cpp
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <gtest/gtest.h>
+
+#include "../linker_block_allocator.h"
+
+#include <unistd.h>
+
+namespace {
+
+struct test_struct_nominal {
+ void* pointer;
+ ssize_t value;
+};
+
+/*
+ * this one has size below allocator cap which is 2*sizeof(void*)
+ */
+struct test_struct_small {
+ char dummy_str[5];
+};
+
+/*
+ * 1009 byte struct (1009 is prime)
+ */
+struct test_struct_larger {
+ char dummy_str[1009];
+};
+
+static size_t kPageSize = sysconf(_SC_PAGE_SIZE);
+};
+
+TEST(linker_allocator, test_nominal) {
+ LinkerTypeAllocator<test_struct_nominal> allocator;
+
+ test_struct_nominal* ptr1 = allocator.alloc();
+ ASSERT_TRUE(ptr1 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr1) % 16);
+ test_struct_nominal* ptr2 = allocator.alloc();
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr2) % 16);
+ ASSERT_TRUE(ptr2 != nullptr);
+ // they should be next to each other.
+ ASSERT_EQ(reinterpret_cast<uint8_t*>(ptr1)+16, reinterpret_cast<uint8_t*>(ptr2));
+
+ ptr1->value = 42;
+
+ allocator.free(ptr1);
+ allocator.free(ptr2);
+}
+
+TEST(linker_allocator, test_small) {
+ LinkerTypeAllocator<test_struct_small> allocator;
+
+ char* ptr1 = reinterpret_cast<char*>(allocator.alloc());
+ char* ptr2 = reinterpret_cast<char*>(allocator.alloc());
+
+ ASSERT_TRUE(ptr1 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr1) % 16);
+ ASSERT_TRUE(ptr2 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr2) % 16);
+ ASSERT_EQ(ptr1+16, ptr2); // aligned to 16
+}
+
+TEST(linker_allocator, test_larger) {
+ LinkerTypeAllocator<test_struct_larger> allocator;
+
+ test_struct_larger* ptr1 = allocator.alloc();
+ test_struct_larger* ptr2 = allocator.alloc();
+
+ ASSERT_TRUE(ptr1 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr1) % 16);
+ ASSERT_TRUE(ptr2 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr2) % 16);
+
+ ASSERT_EQ(reinterpret_cast<uint8_t*>(ptr1) + 1024, reinterpret_cast<uint8_t*>(ptr2));
+
+ // lets allocate until we reach next page.
+ size_t n = kPageSize/sizeof(test_struct_larger) + 1 - 2;
+
+ for (size_t i=0; i<n; ++i) {
+ ASSERT_TRUE(allocator.alloc() != nullptr);
+ }
+
+ test_struct_larger* ptr_to_free = allocator.alloc();
+ ASSERT_TRUE(ptr_to_free != nullptr);
+ allocator.free(ptr1);
+}
+
+static void protect_all() {
+ LinkerTypeAllocator<test_struct_larger> allocator;
+
+ // number of allocs to reach the end of first page
+ size_t n = kPageSize/sizeof(test_struct_larger) - 1;
+ test_struct_larger* page1_ptr = allocator.alloc();
+
+ for (size_t i=0; i<n; ++i) {
+ allocator.alloc();
+ }
+
+ test_struct_larger* page2_ptr = allocator.alloc();
+ allocator.protect_all(PROT_READ);
+ allocator.protect_all(PROT_READ | PROT_WRITE);
+ // check access
+ page2_ptr->dummy_str[23] = 27;
+ page1_ptr->dummy_str[13] = 11;
+
+ allocator.protect_all(PROT_READ);
+ fprintf(stderr, "trying to access protected page");
+
+ // this should result in segmentation fault
+ page1_ptr->dummy_str[11] = 7;
+}
+
+TEST(linker_allocator, test_protect) {
+ testing::FLAGS_gtest_death_test_style = "threadsafe";
+ ASSERT_EXIT(protect_all(), testing::KilledBySignal(SIGSEGV), "trying to access protected page");
+}
+
diff --git a/linker/tests/linker_globals.cpp b/linker/tests/linker_globals.cpp
new file mode 100644
index 0000000..7762a87
--- /dev/null
+++ b/linker/tests/linker_globals.cpp
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// To enable logging
+int g_ld_debug_verbosity = 0;
+
diff --git a/linker/tests/linker_memory_allocator_test.cpp b/linker/tests/linker_memory_allocator_test.cpp
new file mode 100644
index 0000000..5b85536
--- /dev/null
+++ b/linker/tests/linker_memory_allocator_test.cpp
@@ -0,0 +1,203 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <gtest/gtest.h>
+
+#include "../linker_allocator.h"
+
+#include <unistd.h>
+
+namespace {
+
+/*
+ * this one has size below allocator cap which is 2*sizeof(void*)
+ */
+struct test_struct_small {
+ char dummy_str[5];
+};
+
+struct test_struct_large {
+ char dummy_str[1009];
+};
+
+struct test_struct_huge {
+ char dummy_str[73939];
+};
+
+struct test_struct_512 {
+ char dummy_str[503];
+};
+
+};
+
+static size_t kPageSize = sysconf(_SC_PAGE_SIZE);
+
+TEST(linker_memory, test_alloc_0) {
+ LinkerMemoryAllocator allocator;
+ void* ptr = allocator.alloc(0);
+ ASSERT_TRUE(ptr != nullptr);
+ allocator.free(ptr);
+}
+
+TEST(linker_memory, test_free_nullptr) {
+ LinkerMemoryAllocator allocator;
+ allocator.free(nullptr);
+}
+
+TEST(linker_memory, test_realloc) {
+ LinkerMemoryAllocator allocator;
+ uint32_t* array = reinterpret_cast<uint32_t*>(allocator.alloc(512));
+ const size_t array_size = 512 / sizeof(uint32_t);
+
+ uint32_t model[1000];
+
+ model[0] = 1;
+ model[1] = 1;
+
+ for (size_t i = 2; i < 1000; ++i) {
+ model[i] = model[i - 1] + model[i - 2];
+ }
+
+ memcpy(array, model, array_size);
+
+ uint32_t* reallocated_ptr = reinterpret_cast<uint32_t*>(allocator.realloc(array, 1024));
+
+ ASSERT_TRUE(reallocated_ptr != nullptr);
+ ASSERT_TRUE(reallocated_ptr != array);
+
+ ASSERT_TRUE(memcmp(reallocated_ptr, model, array_size) == 0);
+
+ array = reallocated_ptr;
+
+ memcpy(array, model, 2*array_size);
+
+ reallocated_ptr = reinterpret_cast<uint32_t*>(allocator.realloc(array, 62));
+
+ ASSERT_TRUE(reallocated_ptr == array);
+
+ reallocated_ptr = reinterpret_cast<uint32_t*>(allocator.realloc(array, 4000));
+
+ ASSERT_TRUE(reallocated_ptr != nullptr);
+ ASSERT_TRUE(reallocated_ptr != array);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(reallocated_ptr) % 16);
+
+ ASSERT_TRUE(memcmp(reallocated_ptr, model, array_size * 2) == 0);
+
+ array = reallocated_ptr;
+
+ memcpy(array, model, 4000);
+
+ reallocated_ptr = reinterpret_cast<uint32_t*>(allocator.realloc(array, 64000));
+
+ ASSERT_TRUE(reallocated_ptr != nullptr);
+ ASSERT_TRUE(reallocated_ptr != array);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(reallocated_ptr) % 16);
+
+ ASSERT_TRUE(memcmp(reallocated_ptr, model, 4000) == 0);
+
+ ASSERT_EQ(nullptr, allocator.realloc(reallocated_ptr, 0));
+}
+
+TEST(linker_memory, test_small_smoke) {
+ LinkerMemoryAllocator allocator;
+
+ uint8_t zeros[16];
+ memset(zeros, 0, sizeof(zeros));
+
+ test_struct_small* ptr1 =
+ reinterpret_cast<test_struct_small*>(allocator.alloc(sizeof(test_struct_small)));
+ test_struct_small* ptr2 =
+ reinterpret_cast<test_struct_small*>(allocator.alloc(sizeof(test_struct_small)));
+
+ ASSERT_TRUE(ptr1 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr1) % 16);
+ ASSERT_TRUE(ptr2 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr2) % 16);
+
+ ASSERT_EQ(reinterpret_cast<uintptr_t>(ptr1)+16, reinterpret_cast<uintptr_t>(ptr2));
+ ASSERT_TRUE(memcmp(ptr1, zeros, 16) == 0);
+
+ allocator.free(ptr1);
+ allocator.free(ptr2);
+}
+
+TEST(linker_memory, test_huge_smoke) {
+ LinkerMemoryAllocator allocator;
+
+ // this should trigger proxy-to-mmap
+ test_struct_huge* ptr1 =
+ reinterpret_cast<test_struct_huge*>(allocator.alloc(sizeof(test_struct_huge)));
+ test_struct_huge* ptr2 =
+ reinterpret_cast<test_struct_huge*>(allocator.alloc(sizeof(test_struct_huge)));
+
+ ASSERT_TRUE(ptr1 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr1) % 16);
+ ASSERT_TRUE(ptr2 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr2) % 16);
+
+ ASSERT_TRUE(
+ reinterpret_cast<uintptr_t>(ptr1)/kPageSize != reinterpret_cast<uintptr_t>(ptr2)/kPageSize);
+ allocator.free(ptr2);
+ allocator.free(ptr1);
+}
+
+TEST(linker_memory, test_large) {
+ LinkerMemoryAllocator allocator;
+
+ test_struct_large* ptr1 =
+ reinterpret_cast<test_struct_large*>(allocator.alloc(sizeof(test_struct_large)));
+ test_struct_large* ptr2 =
+ reinterpret_cast<test_struct_large*>(allocator.alloc(1024));
+
+ ASSERT_TRUE(ptr1 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr1) % 16);
+ ASSERT_TRUE(ptr2 != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr2) % 16);
+
+ ASSERT_EQ(reinterpret_cast<uintptr_t>(ptr1) + 1024, reinterpret_cast<uintptr_t>(ptr2));
+
+ // let's allocate until we reach the next page.
+ size_t n = kPageSize / sizeof(test_struct_large) + 1 - 2;
+ test_struct_large* objects[n];
+
+ for (size_t i = 0; i < n; ++i) {
+ test_struct_large* obj_ptr =
+ reinterpret_cast<test_struct_large*>(allocator.alloc(sizeof(test_struct_large)));
+ ASSERT_TRUE(obj_ptr != nullptr);
+ objects[i] = obj_ptr;
+ }
+
+ test_struct_large* ptr_to_free =
+ reinterpret_cast<test_struct_large*>(allocator.alloc(sizeof(test_struct_large)));
+
+ ASSERT_TRUE(ptr_to_free != nullptr);
+ ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(ptr_to_free) % 16);
+
+ allocator.free(ptr1);
+
+ for (size_t i=0; i<n; ++i) {
+ allocator.free(objects[i]);
+ }
+
+ allocator.free(ptr2);
+ allocator.free(ptr_to_free);
+}
+
+
diff --git a/linker/tests/linker_sleb128_test.cpp b/linker/tests/linker_sleb128_test.cpp
new file mode 100644
index 0000000..4e29bca
--- /dev/null
+++ b/linker/tests/linker_sleb128_test.cpp
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <gtest/gtest.h>
+
+#include "../linker_sleb128.h"
+
+TEST(linker_sleb128, smoke) {
+ std::vector<uint8_t> encoding;
+ // 624485
+ encoding.push_back(0xe5);
+ encoding.push_back(0x8e);
+ encoding.push_back(0x26);
+ // 0
+ encoding.push_back(0x00);
+ // 1
+ encoding.push_back(0x01);
+ // 63
+ encoding.push_back(0x3f);
+ // 64
+ encoding.push_back(0xc0);
+ encoding.push_back(0x00);
+ // -1
+ encoding.push_back(0x7f);
+ // -624485
+ encoding.push_back(0x9b);
+ encoding.push_back(0xf1);
+ encoding.push_back(0x59);
+ // 2147483647
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0x07);
+ // -2147483648
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x78);
+#if defined(__LP64__)
+ // 9223372036854775807
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0xff);
+ encoding.push_back(0x00);
+ // -9223372036854775808
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x80);
+ encoding.push_back(0x7f);
+#endif
+ sleb128_decoder decoder(&encoding[0], encoding.size());
+
+ EXPECT_EQ(624485U, decoder.pop_front());
+
+ EXPECT_EQ(0U, decoder.pop_front());
+ EXPECT_EQ(1U, decoder.pop_front());
+ EXPECT_EQ(63U, decoder.pop_front());
+ EXPECT_EQ(64U, decoder.pop_front());
+ EXPECT_EQ(static_cast<size_t>(-1), decoder.pop_front());
+ EXPECT_EQ(static_cast<size_t>(-624485), decoder.pop_front());
+ EXPECT_EQ(2147483647U, decoder.pop_front());
+ EXPECT_EQ(static_cast<size_t>(-2147483648), decoder.pop_front());
+#if defined(__LP64__)
+ EXPECT_EQ(9223372036854775807ULL, decoder.pop_front());
+ EXPECT_EQ(static_cast<uint64_t>(-9223372036854775807LL - 1), decoder.pop_front());
+#endif
+}
diff --git a/linker/tests/linker_utils_test.cpp b/linker/tests/linker_utils_test.cpp
new file mode 100644
index 0000000..fd749fa
--- /dev/null
+++ b/linker/tests/linker_utils_test.cpp
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <gtest/gtest.h>
+
+#include "../linker_utils.h"
+
+TEST(linker_utils, normalize_path_smoke) {
+ std::string output;
+ ASSERT_TRUE(normalize_path("/../root///dir/.///dir2/somedir/../zipfile!/dir/dir9//..///afile", &output));
+ ASSERT_EQ("/root/dir/dir2/zipfile!/dir/afile", output);
+
+ ASSERT_TRUE(normalize_path("/../root///dir/.///dir2/somedir/.../zipfile!/.dir/dir9//..///afile", &output));
+ ASSERT_EQ("/root/dir/dir2/somedir/.../zipfile!/.dir/afile", output);
+
+ ASSERT_TRUE(normalize_path("/root/..", &output));
+ ASSERT_EQ("/", output);
+
+ ASSERT_TRUE(normalize_path("/root/notroot/..", &output));
+ ASSERT_EQ("/root/", output);
+
+ ASSERT_TRUE(normalize_path("/a/../../b", &output));
+ ASSERT_EQ("/b", output);
+
+ output = "unchanged";
+ ASSERT_FALSE(normalize_path("root///dir/.///dir2/somedir/../zipfile!/dir/dir9//..///afile", &output));
+ ASSERT_EQ("unchanged", output);
+}
+
+TEST(linker_utils, file_is_in_dir_smoke) {
+ ASSERT_TRUE(file_is_in_dir("/foo/bar/file", "/foo/bar"));
+ ASSERT_FALSE(file_is_in_dir("/foo/bar/file", "/foo"));
+
+ ASSERT_FALSE(file_is_in_dir("/foo/bar/file", "/bar/foo"));
+
+ ASSERT_TRUE(file_is_in_dir("/file", ""));
+ ASSERT_FALSE(file_is_in_dir("/file", "/"));
+}
+
+TEST(linker_utils, file_is_under_dir_smoke) {
+ ASSERT_TRUE(file_is_under_dir("/foo/bar/file", "/foo/bar"));
+ ASSERT_TRUE(file_is_under_dir("/foo/bar/file", "/foo"));
+
+ ASSERT_FALSE(file_is_under_dir("/foo/bar/file", "/bar/foo"));
+
+ ASSERT_TRUE(file_is_under_dir("/file", ""));
+ ASSERT_TRUE(file_is_under_dir("/foo/bar/file", ""));
+ ASSERT_FALSE(file_is_under_dir("/file", "/"));
+ ASSERT_FALSE(file_is_under_dir("/foo/bar/file", "/"));
+}
+
+TEST(linker_utils, parse_zip_path_smoke) {
+ std::string zip_path;
+ std::string entry_path;
+
+ ASSERT_FALSE(parse_zip_path("/not/a/zip/path/file.zip", &zip_path, &entry_path));
+ ASSERT_FALSE(parse_zip_path("/not/a/zip/path/file.zip!path/in/zip", &zip_path, &entry_path));
+ ASSERT_TRUE(parse_zip_path("/zip/path/file.zip!/path/in/zip", &zip_path, &entry_path));
+ ASSERT_EQ("/zip/path/file.zip", zip_path);
+ ASSERT_EQ("path/in/zip", entry_path);
+
+ ASSERT_TRUE(parse_zip_path("/zip/path/file2.zip!/", &zip_path, &entry_path));
+ ASSERT_EQ("/zip/path/file2.zip", zip_path);
+ ASSERT_EQ("", entry_path);
+}
+
+TEST(linker_utils, page_start) {
+ ASSERT_EQ(0x0001000, page_start(0x0001000));
+ ASSERT_EQ(0x3002000, page_start(0x300222f));
+ ASSERT_EQ(0x6001000, page_start(0x6001fff));
+}
+
+TEST(linker_utils, page_offset) {
+ ASSERT_EQ(0x0U, page_offset(0x0001000));
+ ASSERT_EQ(0x22fU, page_offset(0x300222f));
+ ASSERT_EQ(0xfffU, page_offset(0x6001fff));
+}
+
+TEST(linker_utils, safe_add) {
+ int64_t val = 42;
+ ASSERT_FALSE(safe_add(&val, INT64_MAX-20, 21U));
+ ASSERT_EQ(42, val);
+ ASSERT_TRUE(safe_add(&val, INT64_MAX-42, 42U));
+ ASSERT_EQ(INT64_MAX, val);
+ ASSERT_TRUE(safe_add(&val, 2000, 42U));
+ ASSERT_EQ(2042, val);
+}
