From e0916c7fb5da031138014000e6f3a7599db0c348 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 31 Jan 2020 23:43:57 +0100 Subject: [PATCH] avcodec/xvididct: Fix integer overflow in MULT() Fixes: signed integer overflow: 23170 * 95058 cannot be represented in type 'int' Fixes: 20295/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MJPEG_fuzzer-5800212870463488 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 7ccb576191e91b393041b14917f1b681ec75ed3b) Signed-off-by: Michael Niedermayer --- libavcodec/xvididct.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/xvididct.c b/libavcodec/xvididct.c index 1f96ccc35c..cf6963c282 100644 --- a/libavcodec/xvididct.c +++ b/libavcodec/xvididct.c @@ -142,7 +142,7 @@ static int idct_row(short *in, const int *const tab, int rnd) #define TAN3 0xAB0E #define SQRT2 0x5A82 -#define MULT(c, x, n) (((c) * (x)) >> (n)) +#define MULT(c, x, n) ((unsigned)((int)((c) * (unsigned)(x)) >> (n))) // 12b version => #define MULT(c,x, n) ((((c) >> 3) * (x)) >> ((n) - 3)) // 12b zero-testing version: