[FFmpeg-cvslog] avformat/mvdec: Do not set invalid sample rate

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Wed Sep 15 22:00:46 2021 +0200| [737e6bf2162b89d396f4d477bfe8c99f1dd885de] | committer: Michael Niedermayer

avformat/mvdec: Do not set invalid sample rate

Fixes: signed integer overflow: -682581959642593728 * 16 cannot be represented in type 'long'
Fixes: 37883/clusterfuzz-testcase-minimized-ffmpeg_dem_MV_fuzzer-5311691517198336

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Peter Ross <pross at xvid.org>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=737e6bf2162b89d396f4d477bfe8c99f1dd885de
---

 libavformat/mvdec.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/libavformat/mvdec.c b/libavformat/mvdec.c
index b1450e08da..7573087c7c 100644
--- a/libavformat/mvdec.c
+++ b/libavformat/mvdec.c
@@ -156,9 +156,10 @@ static int parse_audio_var(AVFormatContext *avctx, AVStream *st,
     } else if (!strcmp(name, "NUM_CHANNELS")) {
         return set_channels(avctx, st, var_read_int(pb, size));
     } else if (!strcmp(name, "SAMPLE_RATE")) {
-        st->codecpar->sample_rate = var_read_int(pb, size);
-        if (st->codecpar->sample_rate <= 0)
+        int sample_rate = var_read_int(pb, size);
+        if (sample_rate <= 0)
             return AVERROR_INVALIDDATA;
+        st->codecpar->sample_rate = sample_rate;
         avpriv_set_pts_info(st, 33, 1, st->codecpar->sample_rate);
     } else if (!strcmp(name, "SAMPLE_WIDTH")) {
         uint64_t bpc = var_read_int(pb, size) * (uint64_t)8;