avcodec/simple_idct: Fix undefined integer overflow in idct4row()

Fixes: signed integer overflow: -1498310196 - 902891776 cannot be represented in type 'int'
Fixes: 28445/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VC1IMAGE_fuzzer-5075163389493248

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-12-18 00:31:08 +01:00
parent 0af0a80cef
commit 57f7e5caa3

View File

@ -175,7 +175,8 @@ static inline void idct4col_add(uint8_t *dest, ptrdiff_t line_size, const int16_
#define R_SHIFT 11
static inline void idct4row(int16_t *row)
{
int c0, c1, c2, c3, a0, a1, a2, a3;
unsigned c0, c1, c2, c3;
int a0, a1, a2, a3;
a0 = row[0];
a1 = row[1];