| Message ID | 20181129013210.15887-1-michael@niedermayer.cc |
|---|---|
| State | Accepted |
| Commit | 09ec182864d41c990bc18f620eabb77444aeff57 |
| Headers | show |
On Thu, Nov 29, 2018 at 02:32:10AM +0100, Michael Niedermayer wrote: > Frames that small are not valid and of limited use for error concealment, while > being very computationally intensive to process. > > 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@niedermayer.cc> > --- > libavcodec/msmpeg4dec.c | 8 ++++++++ > 1 file changed, 8 insertions(+) will apply this and the othar patch [...]
diff --git a/libavcodec/msmpeg4dec.c b/libavcodec/msmpeg4dec.c index 457a37e745..16b67192b5 100644 --- a/libavcodec/msmpeg4dec.c +++ b/libavcodec/msmpeg4dec.c @@ -412,6 +412,14 @@ int ff_msmpeg4_decode_picture_header(MpegEncContext * s) { int code; + // at minimum one bit per macroblock is required at least in a valid frame, + // we discard frames much smaller than this. Frames smaller than 1/8 of the + // smallest "black/skip" frame generally contain not much recoverable content + // while at the same time they have the highest computational requirements + // per byte + 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){
Frames that small are not valid and of limited use for error concealment, while being very computationally intensive to process. 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@niedermayer.cc> --- libavcodec/msmpeg4dec.c | 8 ++++++++ 1 file changed, 8 insertions(+)