Merge "libfiemap: array boundary check for fiemap.fm_extents[]"
diff --git a/fs_mgr/libfiemap/fiemap_writer.cpp b/fs_mgr/libfiemap/fiemap_writer.cpp
index 71dadd0..275388e 100644
--- a/fs_mgr/libfiemap/fiemap_writer.cpp
+++ b/fs_mgr/libfiemap/fiemap_writer.cpp
@@ -514,6 +514,10 @@
static bool FiemapToExtents(struct fiemap* fiemap, std::vector<struct fiemap_extent>* extents,
std::string_view file_path) {
uint32_t num_extents = fiemap->fm_mapped_extents;
+ if (num_extents == 0) {
+ LOG(ERROR) << "File " << file_path << " has zero extent";
+ return false;
+ }
const struct fiemap_extent* last_extent = &fiemap->fm_extents[num_extents - 1];
if (!IsLastExtent(last_extent)) {
LOG(ERROR) << "FIEMAP did not return a final extent for file: " << file_path
diff --git a/fs_mgr/libfiemap/fiemap_writer_test.cpp b/fs_mgr/libfiemap/fiemap_writer_test.cpp
index b31c78d..c65481b 100644
--- a/fs_mgr/libfiemap/fiemap_writer_test.cpp
+++ b/fs_mgr/libfiemap/fiemap_writer_test.cpp
@@ -258,6 +258,13 @@
EXPECT_EQ(memcmp(actual.data(), data.data(), data.size()), 0);
}
+TEST_F(FiemapWriterTest, CheckEmptyFile) {
+ // Can't get any fiemap_extent out of a zero-sized file.
+ FiemapUniquePtr fptr = FiemapWriter::Open(testfile, 0);
+ EXPECT_EQ(fptr, nullptr);
+ EXPECT_EQ(access(testfile.c_str(), F_OK), -1);
+}
+
TEST_F(SplitFiemapTest, Create) {
auto ptr = SplitFiemap::Create(testfile, 1024 * 768, 1024 * 32);
ASSERT_NE(ptr, nullptr);