avcodec/vp56: Consider the alpha start as end of the prior header

Fixes: Timeout (23sec -> 71ms)
Fixes: 15661/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VP6A_fuzzer-6257865947348992

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Peter Ross <pross@xvid.org>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2019-08-06 23:30:02 +02:00
parent a3e572d96f
commit db78bc1297

View File

@ -572,7 +572,7 @@ int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
VP56Context *s = avctx->priv_data;
AVFrame *const p = s->frames[VP56_FRAME_CURRENT];
int remaining_buf_size = avpkt->size;
int av_uninit(alpha_offset);
int alpha_offset = remaining_buf_size;
int i, res;
int ret;
@ -585,7 +585,7 @@ int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
return AVERROR_INVALIDDATA;
}
res = s->parse_header(s, buf, remaining_buf_size);
res = s->parse_header(s, buf, alpha_offset);
if (res < 0)
return res;