[FFmpeg-cvslog] avformat/mov: Disallow duplicate smdm

[Michael Niedermayer]

ffmpeg | branch: release/4.2 | Michael Niedermayer <michael at niedermayer.cc> | Fri Dec  3 17:42:22 2021 +0100| [1f62d58dae20489c37558f327d9bed47e58870d4] | committer: Michael Niedermayer

avformat/mov: Disallow duplicate smdm

Fixes: memleak
Fixes: 39879/clusterfuzz-testcase-minimized-ffmpeg_dem_MOV_fuzzer-5327819907923968

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit b5ba74053c1ef9f38d9e7b3a036675f06d2b2714)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=1f62d58dae20489c37558f327d9bed47e58870d4
---

 libavformat/mov.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 987b0c0496..b52a72fe30 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -5341,6 +5341,9 @@ static int mov_read_smdm(MOVContext *c, AVIOContext *pb, MOVAtom atom)
         av_log(c->fc, AV_LOG_WARNING, "Unsupported Mastering Display Metadata box version %d\n", version);
         return 0;
     }
+    if (sc->mastering)
+        return AVERROR_INVALIDDATA;
+
     avio_skip(pb, 3); /* flags */
 
     sc->mastering = av_mastering_display_metadata_alloc();