[FFmpeg-cvslog] avformat/rpl: Check the number of streams

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Wed Dec  9 00:49:29 2020 +0100| [0677bdb1f522d0d25b47bca3d8e09ece83083678] | committer: Michael Niedermayer

avformat/rpl: Check the number of streams

Fixes: out of memory access
Fixes: 27787/clusterfuzz-testcase-minimized-ffmpeg_dem_RPL_fuzzer-4743666463408128.fuzz

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda at gmail.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=0677bdb1f522d0d25b47bca3d8e09ece83083678
---

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

diff --git a/libavformat/rpl.c b/libavformat/rpl.c
index c79419d558..b98488c7b1 100644
--- a/libavformat/rpl.c
+++ b/libavformat/rpl.c
@@ -253,6 +253,9 @@ static int rpl_read_header(AVFormatContext *s)
             error |= read_line(pb, line, sizeof(line));
     }
 
+    if (s->nb_streams == 0)
+        return AVERROR_INVALIDDATA;
+
     rpl->frames_per_chunk = read_line_and_int(pb, &error);  // video frames per chunk
     if (vst && rpl->frames_per_chunk > 1 && vst->codecpar->codec_tag != 124)
         av_log(s, AV_LOG_WARNING,