avcodec/wmalosslessdec: move channel check up

Fixes: out of array access
Fixes: 2nd part of 18429/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMALOSSLESS_fuzzer-6210814364614656

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 891bcc4acc)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-01-15 00:32:55 +01:00
parent 2ac4b4fde5
commit cc7760b009
1 changed files with 10 additions and 10 deletions

View File

@ -189,6 +189,16 @@ static av_cold int decode_init(AVCodecContext *avctx)
return AVERROR(EINVAL); return AVERROR(EINVAL);
} }
if (avctx->channels < 0) {
av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
avctx->channels);
return AVERROR_INVALIDDATA;
} else if (avctx->channels > WMALL_MAX_CHANNELS) {
avpriv_request_sample(avctx,
"More than %d channels", WMALL_MAX_CHANNELS);
return AVERROR_PATCHWELCOME;
}
s->max_frame_size = MAX_FRAMESIZE * avctx->channels; s->max_frame_size = MAX_FRAMESIZE * avctx->channels;
s->frame_data = av_mallocz(s->max_frame_size + AV_INPUT_BUFFER_PADDING_SIZE); s->frame_data = av_mallocz(s->max_frame_size + AV_INPUT_BUFFER_PADDING_SIZE);
if (!s->frame_data) if (!s->frame_data)
@ -267,16 +277,6 @@ static av_cold int decode_init(AVCodecContext *avctx)
++s->lfe_channel; ++s->lfe_channel;
} }
if (s->num_channels < 0) {
av_log(avctx, AV_LOG_ERROR, "invalid number of channels %"PRId8"\n",
s->num_channels);
return AVERROR_INVALIDDATA;
} else if (s->num_channels > WMALL_MAX_CHANNELS) {
avpriv_request_sample(avctx,
"More than %d channels", WMALL_MAX_CHANNELS);
return AVERROR_PATCHWELCOME;
}
s->frame = av_frame_alloc(); s->frame = av_frame_alloc();
if (!s->frame) if (!s->frame)
return AVERROR(ENOMEM); return AVERROR(ENOMEM);