avcodec/vmdaudio: Check chunk counts to avoid integer overflow

Fixes: signed integer overflow: 4 * 538976288 cannot be represented in type 'int'
Fixes: 18622/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VMDAUDIO_fuzzer-5092166174507008

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2019-11-08 17:28:27 +01:00
parent 13816a1d08
commit 47d963335e

View File

@ -179,6 +179,9 @@ static int vmdaudio_decode_frame(AVCodecContext *avctx, void *data,
/* drop incomplete chunks */
buf_size = audio_chunks * s->chunk_size;
if (silent_chunks + audio_chunks >= INT_MAX / avctx->block_align)
return AVERROR_INVALIDDATA;
/* get output buffer */
frame->nb_samples = ((silent_chunks + audio_chunks) * avctx->block_align) /
avctx->channels;