[FFmpeg-cvslog] avformat/cafdec: Do not store empty keys in read_info_chunk()

[Michael Niedermayer]

ffmpeg | branch: release/4.2 | Michael Niedermayer <michael at niedermayer.cc> | Sat Mar 19 23:36:22 2022 +0100| [64a756b8f5abfb819674e6268321dae9d324df26] | committer: Michael Niedermayer

avformat/cafdec: Do not store empty keys in read_info_chunk()

Fixes: Timeout
Fixes: 45543/clusterfuzz-testcase-minimized-ffmpeg_dem_CAF_fuzzer-5684953164152832

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 7ec28e1d4cef723485f50f7a08859752b79b570c)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=64a756b8f5abfb819674e6268321dae9d324df26
---

 libavformat/cafdec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavformat/cafdec.c b/libavformat/cafdec.c
index b9260c9074..f0fd326fb6 100644
--- a/libavformat/cafdec.c
+++ b/libavformat/cafdec.c
@@ -243,6 +243,8 @@ static void read_info_chunk(AVFormatContext *s, int64_t size)
         char value[1024];
         avio_get_str(pb, INT_MAX, key, sizeof(key));
         avio_get_str(pb, INT_MAX, value, sizeof(value));
+        if (!*key)
+            continue;
         av_dict_set(&s->metadata, key, value, 0);
     }
 }