diff options
| -rw-r--r-- | linker/linker.cpp | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/linker/linker.cpp b/linker/linker.cpp index b860f70b9..146937a6f 100644 --- a/linker/linker.cpp +++ b/linker/linker.cpp @@ -882,6 +882,60 @@ typedef linked_list_t<soinfo> SoinfoLinkedList; typedef linked_list_t<const char> StringLinkedList; typedef linked_list_t<LoadTask> LoadTaskList; +static soinfo* find_library(const char* name, int rtld_flags, const android_dlextinfo* extinfo); + +// g_ld_all_shim_libs maintains the references to memory as it used +// in the soinfo structures and in the g_active_shim_libs list. + +static std::vector<std::string> g_ld_all_shim_libs; + +// g_active_shim_libs are all shim libs that are still eligible +// to be loaded. We must remove a shim lib from the list before +// we load the library to avoid recursive loops (load shim libA +// for libB where libA also links against libB). + +static linked_list_t<const std::string> g_active_shim_libs; + +static void parse_LD_SHIM_LIBS(const char* path) { + parse_path(path, " :", &g_ld_all_shim_libs); + for (const auto& pair : g_ld_all_shim_libs) { + g_active_shim_libs.push_back(&pair); + } +} + +static bool shim_lib_matches(const char *shim_lib, const char *realpath) { + const char *sep = strchr(shim_lib, '|'); + return sep != nullptr && strncmp(realpath, shim_lib, sep - shim_lib) == 0; +} + +template<typename F> +static bool shim_libs_for_each(const char *const path, F action) { + if (path == nullptr) return true; + INFO("finding shim libs for \"%s\"\n", path); + std::vector<const std::string *> matched; + + g_active_shim_libs.for_each([&](const std::string *a_pair) { + const char *pair = a_pair->c_str(); + if (shim_lib_matches(pair, path)) { + matched.push_back(a_pair); + } + }); + + g_active_shim_libs.remove_if([&](const std::string *a_pair) { + const char *pair = a_pair->c_str(); + return shim_lib_matches(pair, path); + }); + + for (const auto& one_pair : matched) { + const char* const pair = one_pair->c_str(); + const char* sep = strchr(pair, '|'); + INFO("found shim lib \"%s\"\n", sep+1); + soinfo *child = find_library(sep+1, RTLD_GLOBAL, nullptr); + if (! child) return false; + action(child); + } + return true; +} // This function walks down the tree of soinfo dependencies // in breadth-first order and @@ -914,6 +968,12 @@ static bool walk_dependencies_tree(soinfo* root_soinfos[], size_t root_soinfos_s si->get_children().for_each([&](soinfo* child) { visit_list.push_back(child); }); + + if (!shim_libs_for_each(si->get_realpath(), [&](soinfo* child) { + visit_list.push_back(child); + })) { + return false; + } } return true; @@ -3154,9 +3214,11 @@ static ElfW(Addr) __linker_init_post_relocation(KernelArgumentBlock& args, ElfW( // doesn't cost us anything. const char* ldpath_env = nullptr; const char* ldpreload_env = nullptr; + const char* ldshim_libs_env = nullptr; if (!getauxval(AT_SECURE)) { ldpath_env = getenv("LD_LIBRARY_PATH"); ldpreload_env = getenv("LD_PRELOAD"); + ldshim_libs_env = getenv("LD_SHIM_LIBS"); } INFO("[ android linker & debugger ]"); @@ -3210,6 +3272,7 @@ static ElfW(Addr) __linker_init_post_relocation(KernelArgumentBlock& args, ElfW( // 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); + parse_LD_SHIM_LIBS(ldshim_libs_env); somain = si; |