avcodec/wmalosslessdec: Check block_align

Fixes: NULL pointer dereference
Fixes: 18331/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMALOSSLESS_fuzzer-5652847445671936

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2019-10-19 19:18:18 +02:00
parent 673fce6d40
commit c1c799271e

View File

@ -184,8 +184,8 @@ static av_cold int decode_init(AVCodecContext *avctx)
unsigned int channel_mask;
int i, log2_max_num_subframes;
if (!avctx->block_align) {
av_log(avctx, AV_LOG_ERROR, "block_align is not set\n");
if (avctx->block_align <= 0) {
av_log(avctx, AV_LOG_ERROR, "block_align is not set or invalid\n");
return AVERROR(EINVAL);
}