[FFmpeg-devel] [PATCH 1/2] avcodec/dirac_dwt: Fix integer overflows in COMPOSE_DAUB97*

Michael Niedermayer michael at niedermayer.cc
Sun Dec 3 01:39:40 EET 2017


Fixes: 4478/clusterfuzz-testcase-minimized-4752113767809024
Fixes: runtime error: signed integer overflow: -2147483626 + -319489 cannot be represented in type 'int'

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/dirac_dwt.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/libavcodec/dirac_dwt.h b/libavcodec/dirac_dwt.h
index eb5aebc878..50c8b1e394 100644
--- a/libavcodec/dirac_dwt.h
+++ b/libavcodec/dirac_dwt.h
@@ -117,16 +117,16 @@ void ff_spatial_idwt_slice2(DWTContext *d, int y);
     ((unsigned)b4 + ((int)(-2*(b0+(unsigned)b8) + 10*(b1+(unsigned)b7) - 25*(b2+(unsigned)b6) +  81*(b3+(unsigned)b5) + 128) >> 8))
 
 #define COMPOSE_DAUB97iL1(b0, b1, b2)\
-    (b1 - ((int)(1817*(b0 + (unsigned)b2) + 2048) >> 12))
+    ((unsigned)(b1) - ((int)(1817*(b0 + (unsigned)b2) + 2048) >> 12))
 
 #define COMPOSE_DAUB97iH1(b0, b1, b2)\
-    (b1 - ((int)( 113*(b0 + (unsigned)b2) + 64) >> 7))
+    ((unsigned)(b1) - ((int)( 113*(b0 + (unsigned)b2) + 64) >> 7))
 
 #define COMPOSE_DAUB97iL0(b0, b1, b2)\
-    (b1 + ((int)( 217*(b0 + (unsigned)b2) + 2048) >> 12))
+    ((unsigned)(b1) + ((int)( 217*(b0 + (unsigned)b2) + 2048) >> 12))
 
 #define COMPOSE_DAUB97iH0(b0, b1, b2)\
-    (b1 + ((int)(6497*(b0 + (unsigned)b2) + 2048) >> 12))
+    ((unsigned)(b1) + ((int)(6497*(b0 + (unsigned)b2) + 2048) >> 12))
 
 
 #endif /* AVCODEC_DWT_H */
-- 
2.15.0



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