mov: Do not try to parse multiple stsd for the same track

Bug-Id: 1017
CC: libav-stable@libav.org
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

libavformat/mov.c

@@ -1911,6 +1911,12 @@ static int mov_read_stsd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     avio_rb24(pb); /* flags */
     entries = avio_rb32(pb);
 
+    if (sc->extradata) {
+        av_log(c->fc, AV_LOG_ERROR,
+               "Duplicate stsd found in this track.\n");
+        return AVERROR_INVALIDDATA;
+    }
+
     /* Prepare space for hosting multiple extradata. */
     sc->extradata = av_mallocz_array(entries, sizeof(*sc->extradata));
     if (!sc->extradata)