[FFmpeg-cvslog] avcodec/takdsp: Fix integer overflow in decorrelate_sf()

[Michael Niedermayer]

ffmpeg | branch: release/3.2 | Michael Niedermayer <michael at niedermayer.cc> | Mon Mar 28 00:26:06 2022 +0200| [7221c80aae481d139db82dd628c28f5341578050] | committer: Michael Niedermayer

avcodec/takdsp: Fix integer overflow in decorrelate_sf()

Fixes: signed integer overflow: -101 * 71041254 cannot be represented in type 'int'
Fixes: 45938/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TAK_fuzzer-4687974320701440

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 01d8c887f63bcb1f870034ed441504b3daffc645)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7221c80aae481d139db82dd628c28f5341578050
---

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

diff --git a/libavcodec/takdsp.c b/libavcodec/takdsp.c
index 9cb8052596..a8f9dba342 100644
--- a/libavcodec/takdsp.c
+++ b/libavcodec/takdsp.c
@@ -65,7 +65,7 @@ static void decorrelate_sf(int32_t *p1, int32_t *p2, int length, int dshift, int
     for (i = 0; i < length; i++) {
         int32_t a = p1[i];
         int32_t b = p2[i];
-        b         = (unsigned)(dfactor * (b >> dshift) + 128 >> 8) << dshift;
+        b         = (unsigned)((int)(dfactor * (unsigned)(b >> dshift) + 128) >> 8) << dshift;
         p1[i]     = b - a;
     }
 }