| Message ID | 20180826142915.31727-1-michael@niedermayer.cc |
|---|---|
| State | Accepted |
| Commit | 0c88a5d3eb8cd6891a52eb285b37b1458f0b4b16 |
| Headers | show |
On Sun, Aug 26, 2018 at 04:29:15PM +0200, Michael Niedermayer wrote: > This requires us to pre-parse the skip data, as we want to > detect this before allocating all the arrays > > Fixes: Timeout > Fixes: 9708/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV2_fuzzer-5729709861109760 will apply [...]
diff --git a/libavcodec/wmv2dec.c b/libavcodec/wmv2dec.c index ea0e0594b5..4f97d9227c 100644 --- a/libavcodec/wmv2dec.c +++ b/libavcodec/wmv2dec.c @@ -141,6 +141,21 @@ int ff_wmv2_decode_picture_header(MpegEncContext *s) if (s->qscale <= 0) return AVERROR_INVALIDDATA; + if (s->pict_type != AV_PICTURE_TYPE_I && show_bits(&s->gb, 1)) { + GetBitContext gb = s->gb; + int skip_type = get_bits(&gb, 2); + int run = skip_type == SKIP_TYPE_COL ? s->mb_width : s->mb_height; + + while (run > 0) { + int block = FFMIN(run, 25); + if (get_bits(&gb, block) + 1 != 1<<block) + break; + run -= block; + } + if (!run) + return FRAME_SKIPPED; + } + return 0; }
This requires us to pre-parse the skip data, as we want to detect this before allocating all the arrays Fixes: Timeout Fixes: 9708/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV2_fuzzer-5729709861109760 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/wmv2dec.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)