avformat/matroskadec: Check subtitle stream before dereferencing
authorMichael Niedermayer <michael@niedermayer.cc>
Tue, 17 Nov 2015 17:19:01 +0000 (18:19 +0100)
committerMichael Niedermayer <michael@niedermayer.cc>
Thu, 26 Nov 2015 15:58:33 +0000 (16:58 +0100)
Unrecognized streams are not allocated
Fixes: flicker-1.color1.vp91447030769.08.webm

Found-by: Chris Cunningham <chcunningham@google.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit a5034b324cad4c29d47ef285a30b0705e6eb0384)

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
libavformat/matroskadec.c

index 126625f..9107815 100644 (file)
@@ -2971,6 +2971,7 @@ static int matroska_read_seek(AVFormatContext *s, int stream_index,
         tracks[i].audio.buf_timecode   = AV_NOPTS_VALUE;
         tracks[i].end_timecode         = 0;
         if (tracks[i].type == MATROSKA_TRACK_TYPE_SUBTITLE &&
+            tracks[i].stream &&
             tracks[i].stream->discard != AVDISCARD_ALL) {
             index_sub = av_index_search_timestamp(
                 tracks[i].stream, st->index_entries[index].timestamp,