Respect caller DT_RUNPATH in dlopen().
When dlopen-ing a library, add the caller's DT_RUNPATH to the directory search
list. This fixes dlfcn.dt_runpath in bionic-unit-tests-glibc(32|64).
Bug: 21899363
Change-Id: Ife6a7e192939292cf4dc291b7e6b95945761cde3
diff --git a/linker/dlfcn.cpp b/linker/dlfcn.cpp
index ef454ab..4993568 100644
--- a/linker/dlfcn.cpp
+++ b/linker/dlfcn.cpp
@@ -67,9 +67,10 @@
do_android_update_LD_LIBRARY_PATH(ld_library_path);
}
-static void* dlopen_ext(const char* filename, int flags, const android_dlextinfo* extinfo) {
+static void* dlopen_ext(const char* filename, int flags,
+ const android_dlextinfo* extinfo, soinfo* caller) {
ScopedPthreadMutexLocker locker(&g_dl_mutex);
- soinfo* result = do_dlopen(filename, flags, extinfo);
+ soinfo* result = do_dlopen(filename, flags, extinfo, caller);
if (result == nullptr) {
__bionic_format_dlerror("dlopen failed", linker_get_error_buffer());
return nullptr;
@@ -78,11 +79,15 @@
}
void* android_dlopen_ext(const char* filename, int flags, const android_dlextinfo* extinfo) {
- return dlopen_ext(filename, flags, extinfo);
+ void* caller_addr = __builtin_return_address(0);
+ soinfo* caller = find_containing_library(caller_addr);
+ return dlopen_ext(filename, flags, extinfo, caller);
}
void* dlopen(const char* filename, int flags) {
- return dlopen_ext(filename, flags, nullptr);
+ void* caller_addr = __builtin_return_address(0);
+ soinfo* caller = find_containing_library(caller_addr);
+ return dlopen_ext(filename, flags, nullptr, caller);
}
void* dlsym(void* handle, const char* symbol) {
diff --git a/linker/linker.cpp b/linker/linker.cpp
index c6e569a..54fada1 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -1470,9 +1470,17 @@
return global_group;
}
-static bool find_libraries(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) {
+// 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(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;
for (size_t i = 0; i < library_names_count; ++i) {
@@ -1520,7 +1528,7 @@
return false;
}
- if (needed_by != nullptr) {
+ if (needed_by != nullptr && (needed_by != start_with || add_as_children)) {
needed_by->add_child(si);
}
@@ -1547,8 +1555,8 @@
// Step 2: link libraries.
soinfo::soinfo_list_t local_group;
walk_dependencies_tree(
- start_with == nullptr ? soinfos : &start_with,
- start_with == nullptr ? soinfos_count : 1,
+ (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;
@@ -1580,12 +1588,15 @@
return linked;
}
-static soinfo* find_library(const char* name, int rtld_flags, const android_dlextinfo* extinfo) {
+static soinfo* find_library(const char* name, int rtld_flags,
+ const android_dlextinfo* extinfo,
+ soinfo* needed_by) {
soinfo* si;
if (name == nullptr) {
si = somain;
- } else if (!find_libraries(nullptr, &name, 1, &si, nullptr, 0, rtld_flags, extinfo)) {
+ } else if (!find_libraries(needed_by, &name, 1, &si, nullptr, 0, rtld_flags,
+ extinfo, /* add_as_children */ false)) {
return nullptr;
}
@@ -1647,7 +1658,7 @@
TRACE("deprecated (old format of soinfo): %s needs to unload %s",
si->get_realpath(), library_name);
- soinfo* needed = find_library(library_name, RTLD_NOLOAD, nullptr);
+ soinfo* needed = find_library(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.
@@ -1709,7 +1720,7 @@
parse_LD_LIBRARY_PATH(ld_library_path);
}
-soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo) {
+soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo, soinfo *caller) {
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;
@@ -1728,7 +1739,7 @@
}
ProtectedDataGuard guard;
- soinfo* si = find_library(name, flags, extinfo);
+ soinfo* si = find_library(name, flags, extinfo, caller);
if (si != nullptr) {
si->call_constructors();
}
@@ -3272,7 +3283,8 @@
if (needed_libraries_count > 0 &&
!find_libraries(si, needed_library_names, needed_libraries_count, nullptr,
- &g_ld_preloads, ld_preloads_count, RTLD_GLOBAL, nullptr)) {
+ &g_ld_preloads, ld_preloads_count, RTLD_GLOBAL, nullptr,
+ /* add_as_children */ true)) {
__libc_format_fd(2, "CANNOT LINK EXECUTABLE: %s\n", linker_get_error_buffer());
exit(EXIT_FAILURE);
} else if (needed_libraries_count == 0) {
diff --git a/linker/linker.h b/linker/linker.h
index 9bca7f3..b1d2566 100644
--- a/linker/linker.h
+++ b/linker/linker.h
@@ -425,7 +425,7 @@
void do_android_get_LD_LIBRARY_PATH(char*, size_t);
void do_android_update_LD_LIBRARY_PATH(const char* ld_library_path);
-soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo);
+soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo, soinfo *caller);
void do_dlclose(soinfo* si);
int do_dl_iterate_phdr(int (*cb)(dl_phdr_info* info, size_t size, void* data), void* data);
diff --git a/tests/dlfcn_test.cpp b/tests/dlfcn_test.cpp
index 92e3287..00cbdc6 100644
--- a/tests/dlfcn_test.cpp
+++ b/tests/dlfcn_test.cpp
@@ -1072,7 +1072,7 @@
ASSERT_TRUE(fn != nullptr) << dlerror();
void *p = fn();
- ASSERT_TRUE(p == nullptr);
+ ASSERT_TRUE(p != nullptr);
dlclose(handle);
}
