From 896720925a014c891d2e6a9e3e33a5fa6b0fc40c Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 5 Nov 2020 22:14:21 +0100 Subject: [PATCH] avcodec/h264idct_template: Fix integer overflow in ff_h264_chroma422_dc_dequant_idct() Fixes: signed integer overflow: -2105540608 - 2105540608 cannot be represented in type 'int' Fixes: 26870/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-5656647567147008 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 51dfd6f1bdb03bfc7574b12e921fb3b8639ba5cf) Signed-off-by: Michael Niedermayer --- libavcodec/h264idct_template.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/h264idct_template.c b/libavcodec/h264idct_template.c index 1364049fe4..825d2b21ad 100644 --- a/libavcodec/h264idct_template.c +++ b/libavcodec/h264idct_template.c @@ -283,8 +283,8 @@ void FUNCC(ff_h264_chroma422_dc_dequant_idct)(int16_t *_block, int qmul){ dctcoef *block = (dctcoef*)_block; for(i=0; i<4; i++){ - temp[2*i+0] = block[stride*i + xStride*0] + block[stride*i + xStride*1]; - temp[2*i+1] = block[stride*i + xStride*0] - block[stride*i + xStride*1]; + temp[2*i+0] = block[stride*i + xStride*0] + (unsigned)block[stride*i + xStride*1]; + temp[2*i+1] = block[stride*i + xStride*0] - (unsigned)block[stride*i + xStride*1]; } for(i=0; i<2; i++){