Merge "Improve detection of already loaded libraries"
This commit is contained in:
commit
86bc436e20
9 changed files with 459 additions and 158 deletions
|
@ -225,78 +225,26 @@ static unsigned g_libdl_chains[] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 0 };
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static unsigned g_libdl_chains[] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, 0 };
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#endif
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// Defined as global because we do not yet have access
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// to synchronization functions __cxa_guard_* needed
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// to define statics inside functions.
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static soinfo __libdl_info;
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// This is used by the dynamic linker. Every process gets these symbols for free.
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soinfo libdl_info = {
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"libdl.so",
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soinfo* get_libdl_info() {
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if (__libdl_info.name[0] == '\0') {
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// initialize
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strncpy(__libdl_info.name, "libdl.so", sizeof(__libdl_info.name));
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__libdl_info.flags = FLAG_LINKED | FLAG_NEW_SOINFO;
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__libdl_info.strtab = ANDROID_LIBDL_STRTAB;
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__libdl_info.symtab = g_libdl_symtab;
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__libdl_info.nbucket = sizeof(g_libdl_buckets)/sizeof(unsigned);
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__libdl_info.nchain = sizeof(g_libdl_chains)/sizeof(unsigned);
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__libdl_info.bucket = g_libdl_buckets;
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__libdl_info.chain = g_libdl_chains;
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__libdl_info.has_DT_SYMBOLIC = true;
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}
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.phdr = 0,
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.phnum = 0,
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.entry = 0,
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.base = 0,
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.size = 0,
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return &__libdl_info;
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}
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#if !defined(__LP64__)
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.unused1 = 0,
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#endif
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.dynamic = 0,
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#if !defined(__LP64__)
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.unused2 = 0, .unused3 = 0,
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#endif
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.next = 0,
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.flags = FLAG_LINKED,
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.strtab = ANDROID_LIBDL_STRTAB,
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.symtab = g_libdl_symtab,
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.nbucket = sizeof(g_libdl_buckets)/sizeof(unsigned),
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.nchain = sizeof(g_libdl_chains)/sizeof(unsigned),
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.bucket = g_libdl_buckets,
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.chain = g_libdl_chains,
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#if defined(USE_RELA)
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.plt_rela = 0,
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.plt_rela_count = 0,
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.rela = 0,
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.rela_count = 0,
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#else
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.plt_got = 0,
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.plt_rel = 0,
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.plt_rel_count = 0,
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.rel = 0,
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.rel_count = 0,
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#endif
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.preinit_array = 0,
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.preinit_array_count = 0,
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.init_array = 0,
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.init_array_count = 0,
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.fini_array = 0,
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.fini_array_count = 0,
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.init_func = 0,
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.fini_func = 0,
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#if defined(__arm__)
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.ARM_exidx = 0,
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.ARM_exidx_count = 0,
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#elif defined(__mips__)
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.mips_symtabno = 0,
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.mips_local_gotno = 0,
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.mips_gotsym = 0,
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#endif
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.ref_count = 0,
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{ .l_addr = 0, .l_name = 0, .l_ld = 0, .l_next = 0, .l_prev = 0, },
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.constructors_called = false,
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.load_bias = 0,
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#if !defined(__LP64__)
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.has_text_relocations = false,
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#endif
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.has_DT_SYMBOLIC = true,
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};
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75
linker/linked_list.h
Normal file
75
linker/linked_list.h
Normal file
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@ -0,0 +1,75 @@
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/*
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* Copyright (C) 2014 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef __LINKED_LIST_H
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#define __LINKED_LIST_H
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#include "private/bionic_macros.h"
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template<typename T>
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struct LinkedListEntry {
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LinkedListEntry<T>* next;
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T* element;
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};
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/*
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* Represents linked list of objects of type T
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*/
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template<typename T, typename Allocator>
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class LinkedList {
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public:
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LinkedList() : head_(nullptr) {}
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void push_front(T* const element) {
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LinkedListEntry<T>* new_entry = Allocator::alloc();
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new_entry->next = head_;
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new_entry->element = element;
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head_ = new_entry;
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}
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void clear() {
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while (head_ != nullptr) {
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LinkedListEntry<T>* p = head_;
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head_ = head_->next;
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Allocator::free(p);
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}
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}
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template<typename F>
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void for_each(F&& action) {
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for (LinkedListEntry<T>* e = head_; e != nullptr; e = e->next) {
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if (e->element != nullptr) {
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action(e->element);
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}
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}
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}
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template<typename F>
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void remove_if(F&& predicate) {
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LinkedListEntry<T>* e = head_;
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for (LinkedListEntry<T>* e = head_; e != nullptr; e = e->next) {
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if (e->element != nullptr && predicate(e->element)) {
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e->element = nullptr;
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}
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}
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}
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private:
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LinkedListEntry<T>* head_;
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DISALLOW_COPY_AND_ASSIGN(LinkedList);
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};
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#endif // __LINKED_LIST_H
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@ -68,13 +68,11 @@
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static bool soinfo_link_image(soinfo* si, const android_dlextinfo* extinfo);
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static ElfW(Addr) get_elf_exec_load_bias(const ElfW(Ehdr)* elf);
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// We can't use malloc(3) in the dynamic linker. We use a linked list of anonymous
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// maps, each a single page in size. The pages are broken up into as many struct soinfo
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// objects as will fit.
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static LinkerAllocator<soinfo> g_soinfo_allocator;
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static LinkerAllocator<LinkedListEntry<soinfo>> g_soinfo_links_allocator;
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static soinfo* solist = &libdl_info;
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static soinfo* sonext = &libdl_info;
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static soinfo* solist;
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static soinfo* sonext;
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static soinfo* somain; /* main process, always the one after libdl_info */
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static const char* const kDefaultLdPaths[] = {
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@ -263,7 +261,20 @@ void notify_gdb_of_libraries() {
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rtld_db_dlactivity();
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}
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static soinfo* soinfo_alloc(const char* name) {
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LinkedListEntry<soinfo>* SoinfoListAllocator::alloc() {
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return g_soinfo_links_allocator.alloc();
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}
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void SoinfoListAllocator::free(LinkedListEntry<soinfo>* entry) {
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g_soinfo_links_allocator.free(entry);
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}
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static void protect_data(int protection) {
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g_soinfo_allocator.protect_all(protection);
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g_soinfo_links_allocator.protect_all(protection);
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}
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static soinfo* soinfo_alloc(const char* name, struct stat* file_stat) {
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if (strlen(name) >= SOINFO_NAME_LEN) {
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DL_ERR("library name \"%s\" too long", name);
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return NULL;
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@ -274,6 +285,13 @@ static soinfo* soinfo_alloc(const char* name) {
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// Initialize the new element.
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memset(si, 0, sizeof(soinfo));
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strlcpy(si->name, name, sizeof(si->name));
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si->flags = FLAG_NEW_SOINFO;
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if (file_stat != NULL) {
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si->set_st_dev(file_stat->st_dev);
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si->set_st_ino(file_stat->st_ino);
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}
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sonext->next = si;
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sonext = si;
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@ -286,6 +304,10 @@ static void soinfo_free(soinfo* si) {
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return;
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}
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if (si->base != 0 && si->size != 0) {
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munmap(reinterpret_cast<void*>(si->base), si->size);
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}
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soinfo *prev = NULL, *trav;
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TRACE("name %s: freeing soinfo @ %p", si->name, si);
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@ -301,6 +323,9 @@ static void soinfo_free(soinfo* si) {
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return;
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}
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// clear links to/from si
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si->remove_all_links();
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/* prev will never be NULL, because the first entry in solist is
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always the static libdl_info.
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*/
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@ -651,25 +676,52 @@ static soinfo* load_library(const char* name, const android_dlextinfo* extinfo)
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return NULL;
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}
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// Read the ELF header and load the segments.
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ElfReader elf_reader(name, fd);
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struct stat file_stat;
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if (TEMP_FAILURE_RETRY(fstat(fd, &file_stat)) != 0) {
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DL_ERR("unable to stat file for the library %s: %s", name, strerror(errno));
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return NULL;
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}
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// Check for symlink and other situations where
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// file can have different names.
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for (soinfo* si = solist; si != NULL; si = si->next) {
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if (si->get_st_dev() != 0 &&
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si->get_st_ino() != 0 &&
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si->get_st_dev() == file_stat.st_dev &&
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si->get_st_ino() == file_stat.st_ino) {
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TRACE("library \"%s\" is already loaded under different name/path \"%s\" - will return existing soinfo", name, si->name);
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return si;
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}
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}
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// Read the ELF header and load the segments.
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if (!elf_reader.Load(extinfo)) {
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return NULL;
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}
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const char* bname = strrchr(name, '/');
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soinfo* si = soinfo_alloc(bname ? bname + 1 : name);
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soinfo* si = soinfo_alloc(bname ? bname + 1 : name, &file_stat);
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if (si == NULL) {
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return NULL;
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}
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si->base = elf_reader.load_start();
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si->size = elf_reader.load_size();
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si->load_bias = elf_reader.load_bias();
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si->flags = 0;
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si->entry = 0;
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si->dynamic = NULL;
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si->phnum = elf_reader.phdr_count();
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si->phdr = elf_reader.loaded_phdr();
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// At this point we know that whatever is loaded @ base is a valid ELF
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// shared library whose segments are properly mapped in.
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TRACE("[ find_library_internal base=%p size=%zu name='%s' ]",
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reinterpret_cast<void*>(si->base), si->size, si->name);
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if (!soinfo_link_image(si, extinfo)) {
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soinfo_free(si);
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return NULL;
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}
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return si;
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}
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@ -703,23 +755,7 @@ static soinfo* find_library_internal(const char* name, const android_dlextinfo*
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}
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TRACE("[ '%s' has not been loaded yet. Locating...]", name);
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si = load_library(name, extinfo);
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if (si == NULL) {
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return NULL;
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}
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// At this point we know that whatever is loaded @ base is a valid ELF
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// shared library whose segments are properly mapped in.
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TRACE("[ find_library_internal base=%p size=%zu name='%s' ]",
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reinterpret_cast<void*>(si->base), si->size, si->name);
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if (!soinfo_link_image(si, extinfo)) {
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munmap(reinterpret_cast<void*>(si->base), si->size);
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soinfo_free(si);
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return NULL;
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}
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return si;
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return load_library(name, extinfo);
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}
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static soinfo* find_library(const char* name, const android_dlextinfo* extinfo) {
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@ -735,15 +771,21 @@ static int soinfo_unload(soinfo* si) {
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TRACE("unloading '%s'", si->name);
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si->CallDestructors();
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for (ElfW(Dyn)* d = si->dynamic; d->d_tag != DT_NULL; ++d) {
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if (d->d_tag == DT_NEEDED) {
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const char* library_name = si->strtab + d->d_un.d_val;
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TRACE("%s needs to unload %s", si->name, library_name);
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soinfo_unload(find_loaded_library(library_name));
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if ((si->flags | FLAG_NEW_SOINFO) != 0) {
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si->get_children().for_each([&] (soinfo* child) {
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TRACE("%s needs to unload %s", si->name, child->name);
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soinfo_unload(child);
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});
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} else {
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for (ElfW(Dyn)* d = si->dynamic; d->d_tag != DT_NULL; ++d) {
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if (d->d_tag == DT_NEEDED) {
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const char* library_name = si->strtab + d->d_un.d_val;
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TRACE("%s needs to unload %s", si->name, library_name);
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soinfo_unload(find_loaded_library(library_name));
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}
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}
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}
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munmap(reinterpret_cast<void*>(si->base), si->size);
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notify_gdb_of_unload(si);
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si->ref_count = 0;
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soinfo_free(si);
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@ -773,19 +815,20 @@ soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo)
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DL_ERR("invalid extended flags to android_dlopen_ext: %x", extinfo->flags);
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return NULL;
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}
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g_soinfo_allocator.protect_all(PROT_READ | PROT_WRITE);
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protect_data(PROT_READ | PROT_WRITE);
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soinfo* si = find_library(name, extinfo);
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if (si != NULL) {
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si->CallConstructors();
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somain->add_child(si);
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}
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g_soinfo_allocator.protect_all(PROT_READ);
|
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protect_data(PROT_READ);
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return si;
|
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}
|
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|
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int do_dlclose(soinfo* si) {
|
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g_soinfo_allocator.protect_all(PROT_READ | PROT_WRITE);
|
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protect_data(PROT_READ | PROT_WRITE);
|
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int result = soinfo_unload(si);
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g_soinfo_allocator.protect_all(PROT_READ);
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protect_data(PROT_READ);
|
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return result;
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||||
}
|
||||
|
||||
|
@ -1333,7 +1376,7 @@ void soinfo::CallFunction(const char* function_name __unused, linker_function_t
|
|||
|
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// The function may have called dlopen(3) or dlclose(3), so we need to ensure our data structures
|
||||
// are still writable. This happens with our debug malloc (see http://b/7941716).
|
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g_soinfo_allocator.protect_all(PROT_READ | PROT_WRITE);
|
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protect_data(PROT_READ | PROT_WRITE);
|
||||
}
|
||||
|
||||
void soinfo::CallPreInitConstructors() {
|
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|
@ -1365,15 +1408,9 @@ void soinfo::CallConstructors() {
|
|||
name, preinit_array_count);
|
||||
}
|
||||
|
||||
if (dynamic != NULL) {
|
||||
for (ElfW(Dyn)* d = dynamic; d->d_tag != DT_NULL; ++d) {
|
||||
if (d->d_tag == DT_NEEDED) {
|
||||
const char* library_name = strtab + d->d_un.d_val;
|
||||
TRACE("\"%s\": calling constructors in DT_NEEDED \"%s\"", name, library_name);
|
||||
find_loaded_library(library_name)->CallConstructors();
|
||||
}
|
||||
}
|
||||
}
|
||||
get_children().for_each([] (soinfo* si) {
|
||||
si->CallConstructors();
|
||||
});
|
||||
|
||||
TRACE("\"%s\": calling constructors", name);
|
||||
|
||||
|
@ -1392,6 +1429,82 @@ void soinfo::CallDestructors() {
|
|||
CallFunction("DT_FINI", fini_func);
|
||||
}
|
||||
|
||||
void soinfo::add_child(soinfo* child) {
|
||||
if ((this->flags & FLAG_NEW_SOINFO) == 0) {
|
||||
return;
|
||||
}
|
||||
|
||||
this->children.push_front(child);
|
||||
child->parents.push_front(this);
|
||||
}
|
||||
|
||||
void soinfo::remove_all_links() {
|
||||
if ((this->flags & FLAG_NEW_SOINFO) == 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.for_each([&] (const soinfo* child) {
|
||||
return child == this;
|
||||
});
|
||||
});
|
||||
|
||||
// 2. Once everything untied - clear local lists.
|
||||
parents.clear();
|
||||
children.clear();
|
||||
}
|
||||
|
||||
void soinfo::set_st_dev(dev_t dev) {
|
||||
if ((this->flags & FLAG_NEW_SOINFO) == 0) {
|
||||
return;
|
||||
}
|
||||
|
||||
st_dev = dev;
|
||||
}
|
||||
|
||||
void soinfo::set_st_ino(ino_t ino) {
|
||||
if ((this->flags & FLAG_NEW_SOINFO) == 0) {
|
||||
return;
|
||||
}
|
||||
|
||||
st_ino = ino;
|
||||
}
|
||||
|
||||
dev_t soinfo::get_st_dev() {
|
||||
if ((this->flags & FLAG_NEW_SOINFO) == 0) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
return st_dev;
|
||||
};
|
||||
|
||||
ino_t soinfo::get_st_ino() {
|
||||
if ((this->flags & FLAG_NEW_SOINFO) == 0) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
return st_ino;
|
||||
}
|
||||
|
||||
// This is a return on get_children() in case
|
||||
// 'this->flags' does not have FLAG_NEW_SOINFO set.
|
||||
static soinfo::soinfo_list_t g_empty_list;
|
||||
|
||||
soinfo::soinfo_list_t& soinfo::get_children() {
|
||||
if ((this->flags & FLAG_NEW_SOINFO) == 0) {
|
||||
return g_empty_list;
|
||||
}
|
||||
|
||||
return this->children;
|
||||
}
|
||||
|
||||
/* Force any of the closed stdin, stdout and stderr to be associated with
|
||||
/dev/null. */
|
||||
static int nullify_closed_stdio() {
|
||||
|
@ -1715,6 +1828,8 @@ static bool soinfo_link_image(soinfo* si, const android_dlextinfo* extinfo) {
|
|||
library_name, si->name, tmp_err_buf);
|
||||
return false;
|
||||
}
|
||||
|
||||
si->add_child(lsi);
|
||||
*pneeded++ = lsi;
|
||||
}
|
||||
}
|
||||
|
@ -1824,19 +1939,52 @@ static void add_vdso(KernelArgumentBlock& args __unused) {
|
|||
return;
|
||||
}
|
||||
|
||||
soinfo* si = soinfo_alloc("[vdso]");
|
||||
soinfo* si = soinfo_alloc("[vdso]", NULL);
|
||||
|
||||
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->flags = 0;
|
||||
si->load_bias = get_elf_exec_load_bias(ehdr_vdso);
|
||||
|
||||
soinfo_link_image(si, NULL);
|
||||
#endif
|
||||
}
|
||||
|
||||
/*
|
||||
* This is linker soinfo for GDB. See details below.
|
||||
*/
|
||||
static soinfo linker_soinfo_for_gdb;
|
||||
|
||||
/* 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.
|
||||
* Don't use soinfo_alloc(), because the linker shouldn't
|
||||
* be on the soinfo list.
|
||||
*/
|
||||
static void init_linker_info_for_gdb(ElfW(Addr) linker_base) {
|
||||
#if defined(__LP64__)
|
||||
strlcpy(linker_soinfo_for_gdb.name, "/system/bin/linker64", sizeof(linker_soinfo_for_gdb.name));
|
||||
#else
|
||||
strlcpy(linker_soinfo_for_gdb.name, "/system/bin/linker", sizeof(linker_soinfo_for_gdb.name));
|
||||
#endif
|
||||
linker_soinfo_for_gdb.flags = FLAG_NEW_SOINFO;
|
||||
linker_soinfo_for_gdb.base = linker_base;
|
||||
|
||||
/*
|
||||
* 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_soinfo_for_gdb.dynamic, NULL, NULL);
|
||||
insert_soinfo_into_debug_map(&linker_soinfo_for_gdb);
|
||||
}
|
||||
|
||||
/*
|
||||
* This code is called after the linker has linked itself and
|
||||
* fixed it's own GOT. It is safe to make references to externs
|
||||
|
@ -1886,12 +2034,13 @@ static ElfW(Addr) __linker_init_post_relocation(KernelArgumentBlock& args, ElfW(
|
|||
|
||||
// Linker does not call constructors for its own
|
||||
// global variables so we need to initialize
|
||||
// the allocator explicitly.
|
||||
// the allocators explicitly.
|
||||
g_soinfo_allocator.init();
|
||||
g_soinfo_links_allocator.init();
|
||||
|
||||
INFO("[ android linker & debugger ]");
|
||||
|
||||
soinfo* si = soinfo_alloc(args.argv[0]);
|
||||
soinfo* si = soinfo_alloc(args.argv[0], NULL);
|
||||
if (si == NULL) {
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
|
@ -1908,35 +2057,7 @@ static ElfW(Addr) __linker_init_post_relocation(KernelArgumentBlock& args, ElfW(
|
|||
_r_debug.r_map = map;
|
||||
r_debug_tail = map;
|
||||
|
||||
/* 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.
|
||||
* Don't use soinfo_alloc(), because the linker shouldn't
|
||||
* be on the soinfo list.
|
||||
*/
|
||||
{
|
||||
static soinfo linker_soinfo;
|
||||
#if defined(__LP64__)
|
||||
strlcpy(linker_soinfo.name, "/system/bin/linker64", sizeof(linker_soinfo.name));
|
||||
#else
|
||||
strlcpy(linker_soinfo.name, "/system/bin/linker", sizeof(linker_soinfo.name));
|
||||
#endif
|
||||
linker_soinfo.flags = 0;
|
||||
linker_soinfo.base = linker_base;
|
||||
|
||||
/*
|
||||
* 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_soinfo.dynamic, NULL, NULL);
|
||||
insert_soinfo_into_debug_map(&linker_soinfo);
|
||||
}
|
||||
init_linker_info_for_gdb(linker_base);
|
||||
|
||||
// Extract information passed from the kernel.
|
||||
si->phdr = reinterpret_cast<ElfW(Phdr)*>(args.getauxval(AT_PHDR));
|
||||
|
@ -2071,6 +2192,10 @@ static ElfW(Addr) get_elf_exec_load_bias(const ElfW(Ehdr)* elf) {
|
|||
* function, or other GOT reference will generate a segfault.
|
||||
*/
|
||||
extern "C" ElfW(Addr) __linker_init(void* raw_args) {
|
||||
// Initialize static variables.
|
||||
solist = get_libdl_info();
|
||||
sonext = get_libdl_info();
|
||||
|
||||
KernelArgumentBlock args(raw_args);
|
||||
|
||||
ElfW(Addr) linker_addr = args.getauxval(AT_BASE);
|
||||
|
@ -2106,7 +2231,7 @@ extern "C" ElfW(Addr) __linker_init(void* raw_args) {
|
|||
args.abort_message_ptr = &g_abort_message;
|
||||
ElfW(Addr) start_address = __linker_init_post_relocation(args, linker_addr);
|
||||
|
||||
g_soinfo_allocator.protect_all(PROT_READ);
|
||||
protect_data(PROT_READ);
|
||||
|
||||
// Return the address that the calling assembly stub should jump to.
|
||||
return start_address;
|
||||
|
|
|
@ -33,8 +33,10 @@
|
|||
#include <link.h>
|
||||
#include <unistd.h>
|
||||
#include <android/dlext.h>
|
||||
#include <sys/stat.h>
|
||||
|
||||
#include "private/libc_logging.h"
|
||||
#include "linked_list.h"
|
||||
|
||||
#define DL_ERR(fmt, x...) \
|
||||
do { \
|
||||
|
@ -84,6 +86,7 @@
|
|||
#define FLAG_LINKED 0x00000001
|
||||
#define FLAG_EXE 0x00000004 // The main executable
|
||||
#define FLAG_LINKER 0x00000010 // The linker itself
|
||||
#define FLAG_NEW_SOINFO 0x40000000 // new soinfo format
|
||||
|
||||
#define SOINFO_NAME_LEN 128
|
||||
|
||||
|
@ -94,7 +97,20 @@ typedef void (*linker_function_t)();
|
|||
#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);
|
||||
};
|
||||
|
||||
struct soinfo {
|
||||
public:
|
||||
typedef LinkedList<soinfo, SoinfoListAllocator> soinfo_list_t;
|
||||
public:
|
||||
char name[SOINFO_NAME_LEN];
|
||||
const ElfW(Phdr)* phdr;
|
||||
|
@ -179,17 +195,39 @@ struct soinfo {
|
|||
bool has_text_relocations;
|
||||
#endif
|
||||
bool has_DT_SYMBOLIC;
|
||||
|
||||
void CallConstructors();
|
||||
void CallDestructors();
|
||||
void CallPreInitConstructors();
|
||||
|
||||
void add_child(soinfo* child);
|
||||
void remove_all_links();
|
||||
|
||||
void set_st_dev(dev_t st_dev);
|
||||
void set_st_ino(ino_t st_ino);
|
||||
ino_t get_st_ino();
|
||||
dev_t get_st_dev();
|
||||
|
||||
soinfo_list_t& get_children();
|
||||
|
||||
private:
|
||||
void CallArray(const char* array_name, linker_function_t* functions, size_t count, bool reverse);
|
||||
void CallFunction(const char* function_name, linker_function_t function);
|
||||
|
||||
private:
|
||||
// This part of the structure is only available
|
||||
// when FLAG_NEW_SOINFO is set in this->flags.
|
||||
unsigned int version;
|
||||
|
||||
dev_t st_dev;
|
||||
ino_t st_ino;
|
||||
|
||||
// dependency graph
|
||||
soinfo_list_t children;
|
||||
soinfo_list_t parents;
|
||||
|
||||
};
|
||||
|
||||
extern soinfo libdl_info;
|
||||
extern 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);
|
||||
|
|
|
@ -55,8 +55,7 @@ void* LinkerBlockAllocator::alloc() {
|
|||
free_block_list_ = block_info->next_block;
|
||||
}
|
||||
|
||||
block_info->next_block = nullptr;
|
||||
block_info->num_free_blocks = 0;
|
||||
memset(block_info, 0, block_size_);
|
||||
|
||||
return block_info;
|
||||
}
|
||||
|
@ -78,6 +77,8 @@ void LinkerBlockAllocator::free(void* block) {
|
|||
abort();
|
||||
}
|
||||
|
||||
memset(block, 0, block_size_);
|
||||
|
||||
FreeBlockInfo* block_info = reinterpret_cast<FreeBlockInfo*>(block);
|
||||
|
||||
block_info->next_block = free_block_list_;
|
||||
|
@ -100,6 +101,7 @@ void LinkerBlockAllocator::create_new_page() {
|
|||
if (page == MAP_FAILED) {
|
||||
abort(); // oom
|
||||
}
|
||||
memset(page, 0, PAGE_SIZE);
|
||||
|
||||
FreeBlockInfo* first_block = reinterpret_cast<FreeBlockInfo*>(page->bytes);
|
||||
first_block->next_block = free_block_list_;
|
||||
|
|
|
@ -51,6 +51,8 @@ class LinkerBlockAllocator {
|
|||
};
|
||||
|
||||
/*
|
||||
* We can't use malloc(3) in the dynamic linker.
|
||||
*
|
||||
* 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.
|
||||
|
|
|
@ -30,6 +30,7 @@ LOCAL_CFLAGS += -g -Wall -Wextra -Werror -std=gnu++11
|
|||
LOCAL_C_INCLUDES := $(LOCAL_PATH)/../../libc/
|
||||
|
||||
LOCAL_SRC_FILES := \
|
||||
linked_list_test.cpp \
|
||||
linker_allocator_test.cpp \
|
||||
../linker_allocator.cpp
|
||||
|
||||
|
|
97
linker/tests/linked_list_test.cpp
Normal file
97
linker/tests/linked_list_test.cpp
Normal file
|
@ -0,0 +1,97 @@
|
|||
/*
|
||||
* 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));
|
||||
}
|
|
@ -227,6 +227,19 @@ $(libdlext_sym): $(libdlext_origin)
|
|||
ALL_MODULES := \
|
||||
$(ALL_MODULES) $(libdlext_sym)
|
||||
|
||||
ifneq ($(TARGET_2ND_ARCH),)
|
||||
# link 64 bit .so
|
||||
libdlext_origin := $(TARGET_OUT)/lib64/libdlext_test.so
|
||||
libdlext_sym := $(subst libdlext_test,libdlext_test_v2,$(libdlext_origin))
|
||||
$(libdlext_sym): $(libdlext_origin)
|
||||
@echo "Symlink: $@ -> $(notdir $<)"
|
||||
@mkdir -p $(dir $@)
|
||||
$(hide) ln -sf $(notdir $<) $@
|
||||
|
||||
ALL_MODULES := \
|
||||
$(ALL_MODULES) $(libdlext_sym)
|
||||
endif
|
||||
|
||||
libdlext_test_norelro_src_files := \
|
||||
dlext_test_library.cpp \
|
||||
|
||||
|
|
Loading…
Reference in a new issue