[FFmpeg-cvslog] avcodec/dirac_dwt_template: Fix undefined behavior in interleave()

[Michael Niedermayer]

ffmpeg | branch: release/3.3 | Michael Niedermayer <michael at niedermayer.cc> | Thu Jun 14 16:37:32 2018 +0200| [c66723ec498019ab14139905d0b5f0c9af6e377b] | committer: Michael Niedermayer

avcodec/dirac_dwt_template: Fix undefined behavior in interleave()

Fixes: signed integer overflow: 2147483647 + 1 cannot be represented in type 'int'
Fixes: 8697/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DIRAC_fuzzer-5197148130902016

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 575d8ca0260fabac29e5b3541154633569ce2b5d)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c66723ec498019ab14139905d0b5f0c9af6e377b
---

 libavcodec/dirac_dwt_template.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/dirac_dwt_template.c b/libavcodec/dirac_dwt_template.c
index 8c25c1f822..528fc7e9e7 100644
--- a/libavcodec/dirac_dwt_template.c
+++ b/libavcodec/dirac_dwt_template.c
@@ -57,8 +57,8 @@ static av_always_inline void RENAME(interleave)(TYPE *dst, TYPE *src0, TYPE *src
 {
     int i;
     for (i = 0; i < w2; i++) {
-        dst[2*i  ] = (src0[i] + add) >> shift;
-        dst[2*i+1] = (src1[i] + add) >> shift;
+        dst[2*i  ] = (src0[i] + (unsigned)add) >> shift;
+        dst[2*i+1] = (src1[i] + (unsigned)add) >> shift;
     }
 }