[FFmpeg-devel] [PATCH 1/5] avcodec/vp9_superframe_bsf: Check in size

[Michael Niedermayer]

Fixes: Out of array read
Fixes: 45722/clusterfuzz-testcase-minimized-ffmpeg_BSF_VP9_SUPERFRAME_fuzzer-5173378975137792

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/vp9_superframe_bsf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/vp9_superframe_bsf.c b/libavcodec/vp9_superframe_bsf.c
index 57681e29e4..bed9fd4ba2 100644
--- a/libavcodec/vp9_superframe_bsf.c
+++ b/libavcodec/vp9_superframe_bsf.c
@@ -108,7 +108,7 @@ static int vp9_superframe_filter(AVBSFContext *ctx, AVPacket *pkt)
     if (res < 0)
         return res;
 
-    marker = pkt->data[pkt->size - 1];
+    marker = pkt->size ? pkt->data[pkt->size - 1] : 0;
     if ((marker & 0xe0) == 0xc0) {
         int nbytes = 1 + ((marker >> 3) & 0x3);
         int n_frames = 1 + (marker & 0x7), idx_sz = 2 + n_frames * nbytes;
-- 
2.17.1