Merge commit '19730794'

* commit '19730794':
  opusdec: make sure all substreams have the same number of coded samples

Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/opusdec.c

@@ -499,6 +499,12 @@ static int opus_decode_packet(AVCodecContext *avctx, void *data,
                 av_log(avctx, AV_LOG_ERROR, "Error parsing the packet header.\n");
                 return ret;
             }
+            if (coded_samples != s->packet.frame_count * s->packet.frame_duration) {
+                av_log(avctx, AV_LOG_ERROR,
+                       "Mismatching coded sample count in substream %d.\n", i);
+                return AVERROR_INVALIDDATA;
+            }
+
             s->silk_samplerate = get_silk_samplerate(s->packet.config);
         }