avformat/mov: Do not use reference stream in mov_read_sidx() if there is no reference...

Fixes: NULL pointer dereference
Fixes: clusterfuzz-testcase-minimized-audio_decoder_fuzzer-5634316373721088
Reported-by: Chris Cunningham <chcunningham@google.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 73a5ec240e5658910e4d2bb2388f419e3edd2b69..bbd588c70573afabedc38c91a3695785f48ea028 100644 (file)
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -5045,7 +5045,7 @@ static int mov_read_sidx(MOVContext *c, AVIOContext *pb, MOVAtom atom)
                 }
             }
         }
-        for (i = 0; i < c->fc->nb_streams; i++) {
+        if (ref_st) for (i = 0; i < c->fc->nb_streams; i++) {
             st = c->fc->streams[i];
             sc = st->priv_data;
             if (!sc->has_sidx) {