avcodec/h264idct_template: Fix integer overflow in ff_h264_chroma422_dc_dequant_idct()

Fixes: signed integer overflow: 241173056 + 1953511200 cannot be represented in type 'int'
Fixes: 26086/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-5068366420901888
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

diff --git a/libavcodec/h264idct_template.c b/libavcodec/h264idct_template.c
index 5993ae2e6e7dae160037e6855f4b0d94f2d7e6af..f19579a47c865d22ad0eb7589104eed1c4f22dba 100644 (file)
--- a/libavcodec/h264idct_template.c
+++ b/libavcodec/h264idct_template.c
@@ -278,7 +278,7 @@ void FUNCC(ff_h264_chroma422_dc_dequant_idct)(int16_t *_block, int qmul){
     const int stride= 16*2;
     const int xStride= 16;
     int i;
-    int temp[8];
+    unsigned temp[8];
     static const uint8_t x_offset[2]={0, 16};
     dctcoef *block = (dctcoef*)_block;