From 983d119c9b7342b9bf3dff737d520a426a6afd5b Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 20 Nov 2017 03:08:20 +0100 Subject: [PATCH] avcodec/h264idct_template: Fix integer overflow in ff_h264_idct8_add Fixes: signed integer overflow: 452986184 - -2113885312 cannot be represented in type 'int' Fixes: 4196/clusterfuzz-testcase-minimized-5580648594014208 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 9cc926da7d9920d17b76584e7212309ab5c02387) Signed-off-by: Michael Niedermayer --- libavcodec/h264idct_template.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/libavcodec/h264idct_template.c b/libavcodec/h264idct_template.c index 7526bdd812..5993ae2e6e 100644 --- a/libavcodec/h264idct_template.c +++ b/libavcodec/h264idct_template.c @@ -76,10 +76,10 @@ void FUNCC(ff_h264_idct8_add)(uint8_t *_dst, int16_t *_block, int stride){ for( i = 0; i < 8; i++ ) { - const unsigned int a0 = block[i+0*8] + block[i+4*8]; - const unsigned int a2 = block[i+0*8] - block[i+4*8]; - const unsigned int a4 = (block[i+2*8]>>1) - block[i+6*8]; - const unsigned int a6 = (block[i+6*8]>>1) + block[i+2*8]; + const unsigned int a0 = block[i+0*8] + (unsigned)block[i+4*8]; + const unsigned int a2 = block[i+0*8] - (unsigned)block[i+4*8]; + const unsigned int a4 = (block[i+2*8]>>1) - (unsigned)block[i+6*8]; + const unsigned int a6 = (block[i+6*8]>>1) + (unsigned)block[i+2*8]; const unsigned int b0 = a0 + a6; const unsigned int b2 = a2 + a4;