[FFmpeg-devel] [PATCH 2/4] avformat/mov: make sure file_checksum is fully initialized

[Michael Niedermayer]

Fixes: use of uninitialized memory
Fixes: 394990189/clusterfuzz-testcase-minimized-ffmpeg_dem_MOV_fuzzer-6431722199908352

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavformat/mov.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/libavformat/mov.c b/libavformat/mov.c
index ccaa988e4be..8f1c5df3c96 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -1407,7 +1407,9 @@ static int mov_read_adrm(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     avio_read(pb, output, 8); // go to offset 8, absolute position 0x251
     avio_read(pb, input, DRM_BLOB_SIZE);
     avio_read(pb, output, 4); // go to offset 4, absolute position 0x28d
-    avio_read(pb, file_checksum, 20);
+    ret = ffio_read_size(pb, file_checksum, 20);
+    if (ret < 0)
+        goto fail;
 
     // required by external tools
     ff_data_to_hex(checksum_string, file_checksum, sizeof(file_checksum), 1);
-- 
2.50.1