Merge "Handle empty relro segment or incorrectly sized file."
diff --git a/linker/linker_phdr.cpp b/linker/linker_phdr.cpp
index cfeab96..12e9779 100644
--- a/linker/linker_phdr.cpp
+++ b/linker/linker_phdr.cpp
@@ -591,9 +591,12 @@
return -1;
}
off_t file_size = file_stat.st_size;
- void* temp_mapping = mmap(NULL, file_size, PROT_READ, MAP_PRIVATE, fd, 0);
- if (temp_mapping == MAP_FAILED) {
- return -1;
+ void* temp_mapping = NULL;
+ if (file_size > 0) {
+ temp_mapping = mmap(NULL, file_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (temp_mapping == MAP_FAILED) {
+ return -1;
+ }
}
size_t file_offset = 0;
@@ -614,6 +617,13 @@
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 &&
diff --git a/tests/Android.mk b/tests/Android.mk
index 4e82591..9db372a 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -198,17 +198,32 @@
endif
# -----------------------------------------------------------------------------
-# Library used by dlext tests.
+# Library used by dlext tests - with/without GNU RELRO program header
# -----------------------------------------------------------------------------
libdlext_test_src_files := \
dlext_test_library.cpp \
+libdlext_test_ldflags := \
+ -Wl,-z,relro \
+
module := libdlext_test
module_tag := optional
build_type := target
build_target := SHARED_LIBRARY
include $(LOCAL_PATH)/Android.build.mk
+libdlext_test_norelro_src_files := \
+ dlext_test_library.cpp \
+
+libdlext_test_norelro_ldflags := \
+ -Wl,-z,norelro \
+
+module := libdlext_test_norelro
+module_tag := optional
+build_type := target
+build_target := SHARED_LIBRARY
+include $(LOCAL_PATH)/Android.build.mk
+
# -----------------------------------------------------------------------------
# This library used by atexit tests
# -----------------------------------------------------------------------------
diff --git a/tests/dlext_test.cpp b/tests/dlext_test.cpp
index 872cc5b..4b2a5e2 100644
--- a/tests/dlext_test.cpp
+++ b/tests/dlext_test.cpp
@@ -39,6 +39,7 @@
typedef int (*fn)(void);
#define LIBNAME "libdlext_test.so"
+#define LIBNAME_NORELRO "libdlext_test_norelro.so"
#define LIBSIZE 1024*1024 // how much address space to reserve for it
@@ -144,52 +145,88 @@
EXPECT_EQ(4, f());
}
-TEST_F(DlExtTest, RelroShareChildWrites) {
- void* start = mmap(NULL, LIBSIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
- -1, 0);
- ASSERT_TRUE(start != MAP_FAILED);
- android_dlextinfo extinfo;
- extinfo.reserved_addr = start;
- extinfo.reserved_size = LIBSIZE;
+class DlExtRelroSharingTest : public DlExtTest {
+protected:
+ virtual void SetUp() {
+ DlExtTest::SetUp();
+ void* start = mmap(NULL, LIBSIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
+ -1, 0);
+ ASSERT_TRUE(start != MAP_FAILED);
+ extinfo_.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
+ extinfo_.reserved_addr = start;
+ extinfo_.reserved_size = LIBSIZE;
+ extinfo_.relro_fd = -1;
- int relro_fd;
- char relro_file[PATH_MAX];
- const char* android_data = getenv("ANDROID_DATA");
- ASSERT_TRUE(android_data != NULL);
- snprintf(relro_file, sizeof(relro_file), "%s/local/tmp/libdlext_test.relro", android_data);
- relro_fd = open(relro_file, O_CREAT | O_RDWR | O_TRUNC, 0644);
- extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS | ANDROID_DLEXT_WRITE_RELRO;
- ASSERT_NOERROR(relro_fd);
- extinfo.relro_fd = relro_fd;
-
- pid_t pid = fork();
- if (pid == 0) {
- // child process
- void* handle = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
- if (handle == NULL) {
- fprintf(stderr, "in child: %s\n", dlerror());
- exit(1);
- }
- exit(0);
+ const char* android_data = getenv("ANDROID_DATA");
+ ASSERT_TRUE(android_data != NULL);
+ snprintf(relro_file_, sizeof(relro_file_), "%s/local/tmp/libdlext_test.relro", android_data);
}
- // continuing in parent
- ASSERT_NOERROR(close(relro_fd));
- ASSERT_NOERROR(pid);
- int status;
- ASSERT_EQ(pid, waitpid(pid, &status, 0));
- ASSERT_TRUE(WIFEXITED(status));
- ASSERT_EQ(0, WEXITSTATUS(status));
+ virtual void TearDown() {
+ DlExtTest::TearDown();
+ if (extinfo_.relro_fd != -1) {
+ ASSERT_NOERROR(close(extinfo_.relro_fd));
+ }
+ }
- relro_fd = open(relro_file, O_RDONLY);
+ void CreateRelroFile(const char* lib) {
+ int relro_fd = open(relro_file_, O_CREAT | O_RDWR | O_TRUNC, 0644);
+ ASSERT_NOERROR(relro_fd);
+
+ pid_t pid = fork();
+ if (pid == 0) {
+ // child process
+ extinfo_.flags |= ANDROID_DLEXT_WRITE_RELRO;
+ extinfo_.relro_fd = relro_fd;
+ void* handle = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
+ if (handle == NULL) {
+ fprintf(stderr, "in child: %s\n", dlerror());
+ exit(1);
+ }
+ exit(0);
+ }
+
+ // continuing in parent
+ ASSERT_NOERROR(close(relro_fd));
+ ASSERT_NOERROR(pid);
+ int status;
+ ASSERT_EQ(pid, waitpid(pid, &status, 0));
+ ASSERT_TRUE(WIFEXITED(status));
+ ASSERT_EQ(0, WEXITSTATUS(status));
+
+ // reopen file for reading so it can be used
+ relro_fd = open(relro_file_, O_RDONLY);
+ ASSERT_NOERROR(relro_fd);
+ extinfo_.flags |= ANDROID_DLEXT_USE_RELRO;
+ extinfo_.relro_fd = relro_fd;
+ }
+
+ void TryUsingRelro(const char* lib) {
+ handle_ = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
+ ASSERT_DL_NOTNULL(handle_);
+ fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
+ ASSERT_DL_NOTNULL(f);
+ EXPECT_EQ(4, f());
+ }
+
+ android_dlextinfo extinfo_;
+ char relro_file_[PATH_MAX];
+};
+
+TEST_F(DlExtRelroSharingTest, ChildWritesGoodData) {
+ ASSERT_NO_FATAL_FAILURE(CreateRelroFile(LIBNAME));
+ ASSERT_NO_FATAL_FAILURE(TryUsingRelro(LIBNAME));
+}
+
+TEST_F(DlExtRelroSharingTest, ChildWritesNoRelro) {
+ ASSERT_NO_FATAL_FAILURE(CreateRelroFile(LIBNAME_NORELRO));
+ ASSERT_NO_FATAL_FAILURE(TryUsingRelro(LIBNAME_NORELRO));
+}
+
+TEST_F(DlExtRelroSharingTest, RelroFileEmpty) {
+ int relro_fd = open(relro_file_, O_CREAT | O_RDWR | O_TRUNC, 0644);
ASSERT_NOERROR(relro_fd);
- extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS | ANDROID_DLEXT_USE_RELRO;
- extinfo.relro_fd = relro_fd;
- handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
ASSERT_NOERROR(close(relro_fd));
- ASSERT_DL_NOTNULL(handle_);
- fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
- ASSERT_DL_NOTNULL(f);
- EXPECT_EQ(4, f());
+ ASSERT_NO_FATAL_FAILURE(TryUsingRelro(LIBNAME));
}