[FFmpeg-cvslog] avcodec/dcadsp: Fix integer overflow in dmix_add_c()

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sat Jan 30 19:09:36 2021 +0100| [b4ebf483bcbf2e5db6bd29607142741f62598b4e] | committer: Michael Niedermayer

avcodec/dcadsp: Fix integer overflow in dmix_add_c()

Fixes: signed integer overflow: 1515225320 + 759416059 cannot be represented in type 'int'
Fixes: 29256/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DCA_fuzzer-5719088561258496

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

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b4ebf483bcbf2e5db6bd29607142741f62598b4e
---

 libavcodec/dcadsp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/dcadsp.c b/libavcodec/dcadsp.c
index faf244c8ad..9d00ebd281 100644
--- a/libavcodec/dcadsp.c
+++ b/libavcodec/dcadsp.c
@@ -329,7 +329,7 @@ static void dmix_add_c(int32_t *dst, const int32_t *src, int coeff, ptrdiff_t le
     int i;
 
     for (i = 0; i < len; i++)
-        dst[i] += mul15(src[i], coeff);
+        dst[i] += (unsigned)mul15(src[i], coeff);
 }
 
 static void dmix_scale_c(int32_t *dst, int scale, ptrdiff_t len)