typedefint (*fn)(void);
constexpr constchar* kLibName = "libdlext_test.so";
constexpr constchar* kLibNameRecursive = "libdlext_test_recursive.so";
constexpr constchar* kLibNameNoRelro = "libdlext_test_norelro.so";
constexpr constchar* kLibZipSimpleZip = "libdir/libatest_simple_zip.so";
constexpr auto kLibSize = 1024 * 1024; // how much address space to reserve for it
class DlExtTest : public ::testing::Test { protected: void SetUp() override {
handle_ = nullptr; // verify that we don't have the library loaded already void* h = dlopen(kLibName, RTLD_NOW | RTLD_NOLOAD);
ASSERT_TRUE(h == nullptr);
h = dlopen(kLibNameNoRelro, RTLD_NOW | RTLD_NOLOAD);
ASSERT_TRUE(h == nullptr); // call dlerror() to swallow the error, and check it was the one we wanted
ASSERT_EQ(std::string("dlopen failed: library \"") + kLibNameNoRelro + "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
}
// Check if dlsym works after unsuccessful dlopen(). // Supply non-exiting one to make linker visit every soinfo. void* sym = dlsym(RTLD_DEFAULT, "this_symbol_does_not_exist___");
ASSERT_TRUE(sym == nullptr);
close(extinfo.library_fd);
}
TEST_F(DlExtTest, ExtInfoUseOffsetWithoutFd) {
android_dlextinfo extinfo;
extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET; // This offset will not be used, so it doesn't matter.
extinfo.library_fd_offset = 0;
handle_ = android_dlopen_ext("/some/lib/that/does_not_exist", RTLD_NOW, &extinfo);
ASSERT_TRUE(handle_ == nullptr);
ASSERT_STREQ("dlopen failed: invalid extended flag combination (ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET without ANDROID_DLEXT_USE_LIBRARY_FD): 0x20", dlerror());
}
TEST(dlext, android_dlopen_ext_force_load_smoke) {
DlfcnSymlink symlink("android_dlopen_ext_force_load_smoke"); const std::string symlink_name = basename(symlink.get_symlink_path().c_str()); // 1. Open actual file void* handle = dlopen("libdlext_test.so", RTLD_NOW);
ASSERT_DL_NOTNULL(handle); // 2. Open link with force_load flag set
android_dlextinfo extinfo;
extinfo.flags = ANDROID_DLEXT_FORCE_LOAD; void* handle2 = android_dlopen_ext(symlink_name.c_str(), RTLD_NOW, &extinfo);
ASSERT_DL_NOTNULL(handle2);
ASSERT_TRUE(handle != handle2);
dlclose(handle2);
dlclose(handle);
}
TEST(dlext, android_dlopen_ext_force_load_soname_exception) {
DlfcnSymlink symlink("android_dlopen_ext_force_load_soname_exception"); const std::string symlink_name = basename(symlink.get_symlink_path().c_str()); // Check if soname lookup still returns already loaded library // when ANDROID_DLEXT_FORCE_LOAD flag is specified. void* handle = dlopen(symlink_name.c_str(), RTLD_NOW);
ASSERT_DL_NOTNULL(handle);
TEST(dlfcn, dlopen_from_nullptr_android_api_level_28) { // Regression test for http://b/123972211. Testing dlopen(nullptr) when target sdk is P
android_set_application_target_sdk_version(28);
ASSERT_TRUE(dlopen(nullptr, RTLD_NOW) != nullptr);
}
// Test system path translation for backward compatibility. http://b/130219528
TEST(dlfcn, dlopen_system_libicuuc_android_api_level_28) {
android_set_application_target_sdk_version(28);
ASSERT_TRUE(dlopen(PATH_TO_SYSTEM_LIB "libicuuc.so", RTLD_NOW) != nullptr);
ASSERT_TRUE(dlopen(PATH_TO_SYSTEM_LIB "libicui18n.so", RTLD_NOW) != nullptr);
}
uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle_, "dlopen_testlib_taxicab_number"));
ASSERT_DL_NOTNULL(taxicab_number); // Untag the pointer so that it can be compared with start, which will be untagged. void* addr = reinterpret_cast<void*>(untag_address(taxicab_number));
EXPECT_GE(addr, start);
EXPECT_LT(addr, reinterpret_cast<char*>(start) + kLibSize);
EXPECT_EQ(1729U, *taxicab_number);
}
// continuing in parent
ASSERT_NOERROR(close(relro_fd));
ASSERT_NOERROR(pid);
AssertChildExited(pid, 0);
// reopen file for reading so it can be used
relro_fd = open(relro_file, O_RDONLY | O_CLOEXEC);
ASSERT_NOERROR(relro_fd);
extinfo_.flags |= ANDROID_DLEXT_USE_RELRO;
extinfo_.relro_fd = relro_fd;
}
// RELRO file should end up bigger when we use the recursive flag, since it // includes data for more than one library.
ASSERT_GT(with_recursive.st_size, no_recursive.st_size);
}
TEST_F(DlExtRelroSharingTest, ChildWritesNoRelro) {
TemporaryFile tf; // // Use tf to get an unique filename.
ASSERT_NOERROR(close(tf.fd));
// We expect the sharing to save at least 50% of the library's total PSS. // In practice it saves 80%+ for this library in the test.
size_t pss_saved = without_sharing - with_sharing;
size_t expected_min_saved = without_sharing / 2;
EXPECT_LT(expected_min_saved, pss_saved);
// Use destructor of tf to close and unlink the file.
tf.fd = extinfo_.relro_fd;
}
// Create children
pid_t child_pids[CHILDREN]; int childpipe[CHILDREN]; for (int i=0; i<CHILDREN; ++i) { char read_buf; int child_done_pipe[2], parent_done_pipe[2];
ASSERT_NOERROR(pipe(child_done_pipe));
ASSERT_NOERROR(pipe(parent_done_pipe));
pid_t child = fork(); if (child == 0) { // close the 'wrong' ends of the pipes in the child
close(child_done_pipe[0]);
close(parent_done_pipe[1]);
// open the library void* handle; if (share_relro) {
handle = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
} else {
handle = dlopen(lib, RTLD_NOW);
} if (handle == nullptr) {
fprintf(stderr, "in child: %s\n", dlerror()); exit(1);
}
// close write end of child_done_pipe to signal the parent that we're done.
close(child_done_pipe[1]);
// wait for the parent to close parent_done_pipe, then exit
read(parent_done_pipe[0], &read_buf, 1); exit(0);
}
ASSERT_NOERROR(child);
// close the 'wrong' ends of the pipes in the parent
close(child_done_pipe[1]);
close(parent_done_pipe[0]);
// wait for the child to be done
read(child_done_pipe[0], &read_buf, 1);
close(child_done_pipe[0]);
// save the child's pid and the parent_done_pipe
child_pids[i] = child;
childpipe[i] = parent_done_pipe[1];
}
// Sum the PSS of tested library of all the children
size_t total_pss = 0; for (int i=0; i<CHILDREN; ++i) {
size_t child_pss;
ASSERT_NO_FATAL_FAILURE(GetPss(share_relro, lib, relro_file, child_pids[i], &child_pss));
total_pss += child_pss;
}
*pss_out = total_pss;
// Close pipes and wait for children to exit for (int i=0; i<CHILDREN; ++i) {
ASSERT_NOERROR(close(childpipe[i]));
} for (int i = 0; i < CHILDREN; ++i) {
AssertChildExited(child_pids[i], 0);
}
}
ASSERT_FALSE(android_init_anonymous_namespace("", nullptr));
ASSERT_STREQ("android_init_anonymous_namespace failed: error linking namespaces" " \"(anonymous)\"->\"(default)\": the list of shared libraries is empty.",
dlerror());
// This should not have affect search path for default namespace:
ASSERT_TRUE(dlopen(root_lib, RTLD_NOW) == nullptr); void* handle = dlopen(g_public_lib, RTLD_NOW);
ASSERT_TRUE(handle != nullptr) << dlerror();
dlclose(handle);
// dlopen for a public library using an absolute path should work // 1. For isolated namespaces
android_dlextinfo extinfo;
extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
extinfo.library_namespace = ns2;
handle = android_dlopen_ext(lib_public_path.c_str(), RTLD_NOW, &extinfo);
ASSERT_TRUE(handle != nullptr) << dlerror();
ASSERT_TRUE(handle == handle_public);
dlclose(handle);
// 1.1 even if it wasn't loaded before
dlclose(handle_public);
// 2. And for regular namespaces (make sure it does not load second copy of the library)
extinfo.library_namespace = ns1;
handle = android_dlopen_ext(lib_public_path.c_str(), RTLD_NOW, &extinfo);
ASSERT_TRUE(handle != nullptr) << dlerror();
ASSERT_TRUE(handle == handle_public);
dlclose(handle);
// 2.1 Unless it was not loaded before - in which case it will load a duplicate. // TODO(dimitry): This is broken. Maybe we need to deprecate non-isolated namespaces?
dlclose(handle_public);
EXPECT_STREQ("This string is local to root library", ns_get_local_string1());
EXPECT_STREQ("This string is local to root library", ns_get_local_string2());
EXPECT_STREQ("This string is from private namespace", ns_get_private_extern_string1());
EXPECT_STREQ("This string is from private namespace", ns_get_private_extern_string2());
EXPECT_STREQ("This string is from public namespace", ns_get_public_extern_string1());
ASSERT_TRUE(ns_get_public_extern_string1() == ns_get_public_extern_string2());
// and now check that dlopen() does the right thing in terms of preserving namespace
fn_t ns_get_dlopened_string1 = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_dlopened_string"));
ASSERT_TRUE(ns_get_dlopened_string1 != nullptr) << dlerror();
fn_t ns_get_dlopened_string2 = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_dlopened_string"));
ASSERT_TRUE(ns_get_dlopened_string2 != nullptr) << dlerror();
EXPECT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string1());
EXPECT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string2());
// Check if handle2 is still alive (and well)
ASSERT_STREQ("This string is local to root library", ns_get_local_string2());
ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string2());
ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string2());
ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string2());
// Check that relocation worked correctly
fn_t ns_get_internal_extern_string = reinterpret_cast<fn_t>(dlsym(handle, "ns_get_internal_extern_string"));
ASSERT_TRUE(ns_get_internal_extern_string != nullptr) << dlerror();
ASSERT_STREQ("This string is from a library a shared library depends on", ns_get_internal_extern_string());
fn_t internal_extern_string_fn = reinterpret_cast<fn_t>(dlsym(handle, "internal_extern_string"));
ASSERT_TRUE(internal_extern_string_fn != nullptr) << dlerror();
ASSERT_STREQ("This string is from a library a shared library depends on", internal_extern_string_fn());
}
// An app targeting M can open libnativehelper.so because it's on the exempt-list.
android_set_application_target_sdk_version(23); void* handle = android_dlopen_ext("libnativehelper.so", RTLD_NOW, &extinfo);
ASSERT_TRUE(handle != nullptr) << dlerror();
// Check that loader did not load another copy of libdl.so while loading exempted library. void* dlsym_ptr = dlsym(handle, "dlsym");
ASSERT_TRUE(dlsym_ptr != nullptr) << dlerror();
ASSERT_EQ(&dlsym, dlsym_ptr);
dlclose(handle);
// An app targeting N no longer has the exempt-list.
android_set_application_target_sdk_version(24);
handle = android_dlopen_ext("libnativehelper.so", RTLD_NOW, &extinfo);
ASSERT_TRUE(handle == nullptr);
ASSERT_STREQ("dlopen failed: library \"libnativehelper.so\" not found", dlerror());
}
TEST(dlext, ns_cyclic_namespaces) { // Test that ns1->ns2->ns1 link does not break the loader
ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
std::string shared_libs = g_core_shared_libs + ":libthatdoesnotexist.so";
void* handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
ASSERT_TRUE(handle2 == nullptr); constchar* error = dlerror();
ASSERT_MATCH(error,
R"(dlopen failed: library "libnstest_private_external.so" not found: needed by )"
R"(\S+libnstest_root_not_isolated.so in namespace private_isolated1)");
// Check dlopen by absolute path
handle2 = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
ASSERT_TRUE(handle2 == nullptr);
ASSERT_EQ("dlopen failed: library \"" + lib_private_external_path + "\" needed" " or dlopened by \"" + android::base::GetExecutablePath() + "\" is not accessible" " for the namespace \"private_isolated1\"", dlerror());
extinfo.library_namespace = ns_isolated2;
// this should work because isolation_path for private_isolated2 includes GetTestLibRoot()
handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
ASSERT_TRUE(handle2 != nullptr) << dlerror();
dlclose(handle2);
// create a parent namespace to use instead of the default namespace. This is // to make this test be independent from the configuration of the default // namespace.
android_namespace_t* ns_parent =
android_create_namespace("parent",
nullptr,
nullptr,
ANDROID_NAMESPACE_TYPE_REGULAR,
nullptr,
nullptr);
ASSERT_TRUE(ns_parent != nullptr) << dlerror();
ASSERT_TRUE(android_link_namespaces(ns_parent, nullptr, g_core_shared_libs.c_str())) << dlerror();
// preload this library to the parent namespace to check if it // is shared later on. void* handle_dlopened =
android_dlopen_ext((GetTestLibRoot() + "/private_namespace_libs/libnstest_dlopened.so").c_str(), RTLD_NOW, &extinfo);
ASSERT_TRUE(handle_dlopened != nullptr) << dlerror();
// create two child namespaces of 'ns_parent'. One with regular, the other // with isolated & shared.
android_namespace_t* ns_not_isolated =
android_create_namespace("private",
nullptr,
(GetTestLibRoot() + "/private_namespace_libs").c_str(),
ANDROID_NAMESPACE_TYPE_REGULAR,
nullptr,
ns_parent);
ASSERT_TRUE(ns_not_isolated != nullptr) << dlerror();
ASSERT_TRUE(android_link_namespaces(ns_not_isolated, ns_parent, g_public_lib)) << dlerror();
ASSERT_TRUE(android_link_namespaces(ns_not_isolated, nullptr, g_core_shared_libs.c_str())) << dlerror();
// Load lib_private_external_path to the parent namespace // (it should remain invisible for the isolated namespaces after this) void* handle = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
ASSERT_TRUE(handle != nullptr) << dlerror();
ASSERT_STREQ("This string is local to root library", ns_get_local_string());
ASSERT_STREQ("This string is local to root library", ns_get_local_string_shared());
ASSERT_TRUE(ns_get_local_string() != ns_get_local_string_shared());
ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string());
ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string_shared());
ASSERT_TRUE(ns_get_private_extern_string() != ns_get_private_extern_string_shared());
ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string());
ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string_shared());
ASSERT_TRUE(ns_get_public_extern_string() == ns_get_public_extern_string_shared());
// 1. Load a library in ns_shared to check that it has inherited // search path and the link to the default namespace.
android_dlextinfo extinfo;
extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
extinfo.library_namespace = ns_shared;
dlclose(handle);
} // 2. Load another test library by absolute path to check that // it has inherited permitted_when_isolated_path
{ void* handle = android_dlopen_ext(
(GetTestLibRoot() + "/public_namespace_libs/libnstest_public.so").c_str(),
RTLD_NOW,
&extinfo);
ASSERT_TRUE(handle != nullptr) << dlerror(); constchar** ns_public_extern_string = static_cast<constchar**>(dlsym(handle, "g_public_extern_string"));
ASSERT_TRUE(ns_public_extern_string != nullptr) << dlerror();
ASSERT_STREQ("This string is from public namespace", *ns_public_extern_string);
dlclose(handle);
}
// 3. Check that it is still isolated.
{ void* handle = android_dlopen_ext(
(GetTestLibRoot() + "/libtest_empty.so").c_str(),
RTLD_NOW,
&extinfo);
// preload this library to the default namespace to check if it // is shared later on. void* handle_dlopened =
dlopen((GetTestLibRoot() + "/private_namespace_libs/libnstest_dlopened.so").c_str(), RTLD_NOW);
ASSERT_TRUE(handle_dlopened != nullptr) << dlerror();
// And now check that the library cannot be found by soname (and is no longer loaded)
handle = android_dlopen_ext("libnstest_dlopened.so", RTLD_NOW | RTLD_NOLOAD, &extinfo);
ASSERT_TRUE(handle == nullptr)
<< "Error: libnstest_dlopened.so is still accessible in shared namespace";
handle = android_dlopen_ext((GetTestLibRoot() + "/private_namespace_libs/libnstest_dlopened.so").c_str(),
RTLD_NOW | RTLD_NOLOAD, &extinfo);
ASSERT_TRUE(handle == nullptr)
<< "Error: libnstest_dlopened.so is still accessible in shared namespace";
handle = dlopen("libnstest_dlopened.so", RTLD_NOW | RTLD_NOLOAD);
ASSERT_TRUE(handle == nullptr)
<< "Error: libnstest_dlopened.so is still accessible in default namespace";
handle = dlopen((GetTestLibRoot() + "/private_namespace_libs/libnstest_dlopened.so").c_str(),
RTLD_NOW | RTLD_NOLOAD);
ASSERT_TRUE(handle == nullptr)
<< "Error: libnstest_dlopened.so is still accessible in default namespace";
// Now lets see if the soinfo area gets reused in the wrong way: // load a library to default namespace. const std::string lib_public_path = GetTestLibRoot() + "/public_namespace_libs/" + g_public_lib; void* handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
ASSERT_TRUE(handle_public != nullptr) << dlerror();
// try to find it in shared namespace
handle = android_dlopen_ext(g_public_lib, RTLD_NOW | RTLD_NOLOAD, &extinfo);
ASSERT_TRUE(handle == nullptr)
<< "Error: " << g_public_lib << " is accessible in shared namespace";
}
// and ns2 should fail
extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
extinfo.library_namespace = ns2;
handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
ASSERT_TRUE(handle1 == nullptr);
ASSERT_MATCH(
dlerror(),
R"(dlopen failed: library "libnstest_public.so" not found: needed by \S+libnstest_root.so)"
R"( in namespace isolated2)");
}
TEST(dlext, ns_inaccessible_error_message) { // We set up 2 namespaces (a and b) and link a->b with a shared library // libtestshared.so. Then try to dlopen different library with the same // name from in namespace a. Note that library should not be accessible // in either namespace but since it's soname is in the list of shared libs // the linker will attempt to find it in linked namespace. // // Check the error message and make sure it mentions correct namespace name.
ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
// Test android_link_namespaces()
ASSERT_FALSE(android_link_namespaces(nullptr, nullptr, "libc.so"));
ASSERT_STREQ("android_link_namespaces failed: error linking namespaces: namespace_from is null.",
dlerror());
ASSERT_FALSE(android_link_namespaces(ns, nullptr, nullptr));
ASSERT_STREQ("android_link_namespaces failed: " "error linking namespaces \"private\"->\"(default)\": " "the list of shared libraries is empty.", dlerror());
ASSERT_FALSE(android_link_namespaces(ns, nullptr, ""));
ASSERT_STREQ("android_link_namespaces failed: " "error linking namespaces \"private\"->\"(default)\": " "the list of shared libraries is empty.", dlerror());
// Test __loader_android_link_namespaces_all_libs()
ASSERT_FALSE(__loader_android_link_namespaces_all_libs(nullptr, nullptr));
ASSERT_STREQ("android_link_namespaces_all_libs failed: " "error linking namespaces: namespace_from is null.", dlerror());
// we are going to copy this library to anonymous mmap and call the copy of ns_get_dlopened_string void* handle = android_dlopen_ext(private_library_absolute_path.c_str(), RTLD_NOW, &extinfo);
ASSERT_TRUE(handle != nullptr) << dlerror();
if (!has_executable_segment) { // For some natively bridged environments this code might be missing // the executable flag. This is because the guest code is not supposed // to be executed directly and making it non-executable is more secure. // In this case we assume the segment with the function is executable. for (auto& rec : maps_to_copy) { if (ns_get_dlopened_string_addr >= rec.addr_start &&
ns_get_dlopened_string_addr < rec.addr_end) {
ASSERT_TRUE((rec.perms & PROT_WRITE) == 0);
rec.perms |= PROT_EXEC; break;
}
}
}
struct stat file_stat; int ret = TEMP_FAILURE_RETRY(stat(private_library_absolute_path.c_str(), &file_stat));
ASSERT_EQ(ret, 0) << "Failed to stat library";
size_t file_size = file_stat.st_size;
{ // Disable MTE while copying the PROT_MTE-protected global variables from // the existing mappings. We don't really care about turning on PROT_MTE for // the new copy of the mappings, as this isn't the behaviour under test and // tags will be ignored. This only applies for MTE-enabled devices.
ScopedDisableMTE disable_mte_for_copying_global_variables; for (constauto& rec : maps_to_copy) {
uintptr_t offset = rec.addr_start - addr_start;
size_t size = rec.addr_end - rec.addr_start; void* addr = reinterpret_cast<void*>(reserved_addr + offset); void* map =
mmap(addr, size, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0);
ASSERT_TRUE(map != MAP_FAILED); // Attempting the below memcpy from a portion of the map that is off the end of // the backing file will cause the kernel to throw a SIGBUS
size_t _size =
::android::procinfo::MappedFileSize(rec.addr_start, rec.addr_end, rec.offset, file_size);
memcpy(map, reinterpret_cast<void*>(rec.addr_start), _size);
mprotect(map, size, rec.perms);
}
}
// call the function copy
uintptr_t ns_get_dlopened_string_offset = ns_get_dlopened_string_addr - addr_start;
fn_t ns_get_dlopened_string_anon = reinterpret_cast<fn_t>(reserved_addr + ns_get_dlopened_string_offset);
ASSERT_STREQ("This string is from private namespace (dlopened library)",
ns_get_dlopened_string_anon());
// They should belong to different namespaces (private and anonymous)
ASSERT_STREQ("This string is from private namespace (dlopened library)",
ns_get_dlopened_string_private());
// Add the main libns_hidden_child_*.so libraries to the search path of the default namespace.
std::string env = "LD_LIBRARY_PATH=" + GetTestLibRoot();
eth.SetEnv({ env.c_str(), nullptr });
eth.Run([&]() { execve(helper.c_str(), eth.GetArgs(), eth.GetEnv()); }, 0, "public_function is non-null\n" "internal_function is null\n");
}
TEST(dlext, dlopen_handle_value_platform) { void* handle = dlopen("libtest_dlsym_from_this.so", RTLD_NOW | RTLD_LOCAL);
ASSERT_TRUE((reinterpret_cast<uintptr_t>(handle) & 1) != 0)
<< "dlopen should return odd value for the handle";
dlclose(handle);
}
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