[FFmpeg-cvslog] avcodec/dirac_dwt: Fix integer overflow in COMPOSE_DD97iH0() and COMPOSE_DD137iL0()

[Michael Niedermayer]

ffmpeg | branch: release/2.8 | Michael Niedermayer <michael at niedermayer.cc> | Fri Dec 22 03:06:14 2017 +0100| [d0967e3faf4d0d90122cc46297fc0b9e86001102] | committer: Michael Niedermayer

avcodec/dirac_dwt: Fix integer overflow in COMPOSE_DD97iH0() and COMPOSE_DD137iL0()

Fixes: runtime error: signed integer overflow: 2147483646 + 33554433 cannot be represented in type 'int'
Fixes: 4563/clusterfuzz-testcase-minimized-5438979567517696

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 4d70fbeec8cbab072b3a9b9f760b8deaaef240f2)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=d0967e3faf4d0d90122cc46297fc0b9e86001102
---

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

diff --git a/libavcodec/dirac_dwt.h b/libavcodec/dirac_dwt.h
index 7189818d05..acefd3b3d3 100644
--- a/libavcodec/dirac_dwt.h
+++ b/libavcodec/dirac_dwt.h
@@ -90,10 +90,10 @@ void ff_spatial_idwt_slice2(DWTContext *d, int y);
     (b1 + ((int)(b0 + (unsigned)(b2) + 1) >> 1))
 
 #define COMPOSE_DD97iH0(b0, b1, b2, b3, b4)\
-    (b2 + ((int)(-b0 + 9U*b1 + 9U*b3 - b4 + 8) >> 4))
+    (int)(((unsigned)(b2) + ((int)(-b0 + 9U*b1 + 9U*b3 - b4 + 8) >> 4)))
 
 #define COMPOSE_DD137iL0(b0, b1, b2, b3, b4)\
-    (b2 - ((int)(-b0 + 9U*b1 + 9U*b3 - b4 + 16) >> 5))
+    (int)(((unsigned)(b2) - ((int)(-b0 + 9U*b1 + 9U*b3 - b4 + 16) >> 5)))
 
 #define COMPOSE_HAARiL0(b0, b1)\
     (b0 - ((b1 + 1) >> 1))