[FFmpeg-cvslog] avcodec/wmaprodec: Check that the streams channels do not exceed the overall channels

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sat Oct 12 18:32:08 2019 +0200| [e418b315ddd0505e707860f8cc8b796ce06f3458] | committer: Michael Niedermayer

avcodec/wmaprodec: Check that the streams channels do not exceed the overall channels

Fixes: NULL pointer dereference
Fixes: 18075/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_XMA1_fuzzer-5708262036471808
Fixes: 18087/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_XMA1_fuzzer-5740627634946048

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda at gmail.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e418b315ddd0505e707860f8cc8b796ce06f3458
---

 libavcodec/wmaprodec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/wmaprodec.c b/libavcodec/wmaprodec.c
index 5c18479b3b..41ca792548 100644
--- a/libavcodec/wmaprodec.c
+++ b/libavcodec/wmaprodec.c
@@ -437,7 +437,7 @@ static av_cold int decode_init(WMAProDecodeCtx *s, AVCodecContext *avctx, int nu
         av_log(avctx, AV_LOG_ERROR, "invalid number of channels per XMA stream %d\n",
                s->nb_channels);
         return AVERROR_INVALIDDATA;
-    } else if (s->nb_channels > WMAPRO_MAX_CHANNELS) {
+    } else if (s->nb_channels > WMAPRO_MAX_CHANNELS || s->nb_channels > avctx->channels) {
         avpriv_request_sample(avctx,
                               "More than %d channels", WMAPRO_MAX_CHANNELS);
         return AVERROR_PATCHWELCOME;