ffmpeg | branch: release/3.2 | Michael Niedermayer <mich...@niedermayer.cc> | Tue Nov 27 23:37:03 2018 +0100| [4ff4fd41791c4cb22dd87cb115bd6f7980f4a73a] | committer: Michael Niedermayer
avcodec/wmv2dec: Skip I frame if its smaller than 1/8 of the minimal size Frames that small are not valid and of limited use for error concealment, while being very computationally intensive to process. Fixes: Timeout Fixes: 11168/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV2_fuzzer-5733782032744448 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> (cherry picked from commit d6f4341522c3eafb046c47b115d79ce684a899fc) Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=4ff4fd41791c4cb22dd87cb115bd6f7980f4a73a --- libavcodec/wmv2dec.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/libavcodec/wmv2dec.c b/libavcodec/wmv2dec.c index 225e30ab5a..1aa0da0271 100644 --- a/libavcodec/wmv2dec.c +++ b/libavcodec/wmv2dec.c @@ -166,6 +166,14 @@ int ff_wmv2_decode_secondary_picture_header(MpegEncContext *s) } s->dc_table_index = get_bits1(&s->gb); + + // 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; } s->inter_intra_pred = 0; s->no_rounding = 1; _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
