[FFmpeg-cvslog] avformat/dcstr: Check sample rate

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Wed Mar  3 10:49:03 2021 +0100| [fdcb966f4a3c6f872891b8dd554e3652b9e02d4f] | committer: Michael Niedermayer

avformat/dcstr: Check sample rate

Fixes: signed integer overflow: -1300248894420254720 * 16 cannot be represented in type 'long'
Fixes: 30879/clusterfuzz-testcase-minimized-ffmpeg_dem_DCSTR_fuzzer-5094464215449600

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=fdcb966f4a3c6f872891b8dd554e3652b9e02d4f
---

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

diff --git a/libavformat/dcstr.c b/libavformat/dcstr.c
index 9041a86539..9ddccc7f2d 100644
--- a/libavformat/dcstr.c
+++ b/libavformat/dcstr.c
@@ -43,6 +43,8 @@ static int dcstr_read_header(AVFormatContext *s)
     st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
     st->codecpar->channels    = avio_rl32(s->pb);
     st->codecpar->sample_rate = avio_rl32(s->pb);
+    if (st->codecpar->sample_rate <= 0)
+        return AVERROR_INVALIDDATA;
     codec                  = avio_rl32(s->pb);
     align                  = avio_rl32(s->pb);
     avio_skip(s->pb, 4);