[FFmpeg-devel] [PATCH 2/3] avcodec/dirac_dwt: Fix multiple overflows in 9/7 lifting

Michael Niedermayer michael at niedermayer.cc
Fri Sep 1 20:56:11 EEST 2017


Fixes: runtime error: signed integer overflow: 1073901567 + 1073901567 cannot be represented in type 'int'
Fixes: 3124/clusterfuzz-testcase-minimized-454643435752652

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 e715e53bc4..adf5178714 100644
--- a/libavcodec/dirac_dwt.h
+++ b/libavcodec/dirac_dwt.h
@@ -117,16 +117,16 @@ void ff_spatial_idwt_slice2(DWTContext *d, int y);
     (b4 + ((-2*(b0+b8) + 10*(b1+b7) - 25*(b2+b6) + 81*(b3+b5) + 128) >> 8))
 
 #define COMPOSE_DAUB97iL1(b0, b1, b2)\
-    (b1 - ((int)(1817U*(b0 + b2) + 2048) >> 12))
+    (b1 - ((int)(1817*(b0 + (unsigned)b2) + 2048) >> 12))
 
 #define COMPOSE_DAUB97iH1(b0, b1, b2)\
-    (b1 - ((int)( 113U*(b0 + b2) + 64) >> 7))
+    (b1 - ((int)( 113*(b0 + (unsigned)b2) + 64) >> 7))
 
 #define COMPOSE_DAUB97iL0(b0, b1, b2)\
-    (b1 + ((int)( 217U*(b0 + b2) + 2048) >> 12))
+    (b1 + ((int)( 217*(b0 + (unsigned)b2) + 2048) >> 12))
 
 #define COMPOSE_DAUB97iH0(b0, b1, b2)\
-    (b1 + ((int)(6497U*(b0 + b2) + 2048) >> 12))
+    (b1 + ((int)(6497*(b0 + (unsigned)b2) + 2048) >> 12))
 
 
 #endif /* AVCODEC_DWT_H */
-- 
2.14.1



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