[FFmpeg-devel] [PATCH 1/2] avcodec/msmpeg4dec: Skip frame if its smaller than 1/8 of the minimal size

[Michael Niedermayer]

Fixes: Timeout
Fixes: 11318/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MSMPEG4V1_fuzzer-5710884555456512

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/msmpeg4dec.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/msmpeg4dec.c b/libavcodec/msmpeg4dec.c
index 457a37e745..d278540ec2 100644
--- a/libavcodec/msmpeg4dec.c
+++ b/libavcodec/msmpeg4dec.c
@@ -412,6 +412,9 @@ int ff_msmpeg4_decode_picture_header(MpegEncContext * s)
 {
     int code;
 
+    if (get_bits_left(&s->gb) * 8LL < (s->width+15)/16 * ((s->height+15)/16))
+        return AVERROR_INVALIDDATA;
+
     if(s->msmpeg4_version==1){
         int start_code = get_bits_long(&s->gb, 32);
         if(start_code!=0x00000100){
-- 
2.19.2