[FFmpeg-cvslog] mxfdec: fix NULL pointer dereference

[Andreas Cadhalpun]

ffmpeg | branch: release/3.1 | Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com> | Sat Nov  5 00:17:53 2016 +0100| [50d34cbf5ac86a42d3273765ce8292a06ae11158] | committer: Andreas Cadhalpun

mxfdec: fix NULL pointer dereference

Metadata streams have priv_data set to NULL.

Reviewed-by: Michael Niedermayer <michael at niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
(cherry picked from commit 0efb6106118c17308b3fdc3190f5e5bf84b01d5c)
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=50d34cbf5ac86a42d3273765ce8292a06ae11158
---

 libavformat/mxfdec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index 17ffdf5..a7cc9b8 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -383,7 +383,7 @@ static int mxf_get_stream_index(AVFormatContext *s, KLVPacket *klv)
     for (i = 0; i < s->nb_streams; i++) {
         MXFTrack *track = s->streams[i]->priv_data;
         /* SMPTE 379M 7.3 */
-        if (!memcmp(klv->key + sizeof(mxf_essence_element_key), track->track_number, sizeof(track->track_number)))
+        if (track && !memcmp(klv->key + sizeof(mxf_essence_element_key), track->track_number, sizeof(track->track_number)))
             return i;
     }
     /* return 0 if only one stream, for OP Atom files with 0 as track number */