From a234b5ade3ca6cde805b92b8b6ecacf693460a8c Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Fri, 5 May 2017 22:17:59 +0200
Subject: [PATCH] avcodec/mdec: Fix signed integer overflow: 28835400 * 83
cannot be represented in type 'int'
Fixes: 1346/clusterfuzz-testcase-minimized-5776732600664064
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
libavcodec/mdec.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/libavcodec/mdec.c b/libavcodec/mdec.c
index 42bd561cd7..8e28aa04f0 100644
--- a/libavcodec/mdec.c
+++ b/libavcodec/mdec.c
@@ -111,11 +111,11 @@ static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
j = scantable[i];
if (level < 0) {
level = -level;
- level = (level * qscale * quant_matrix[j]) >> 3;
+ level = (level * (unsigned)qscale * quant_matrix[j]) >> 3;
level = (level - 1) | 1;
level = -level;
} else {
- level = (level * qscale * quant_matrix[j]) >> 3;
+ level = (level * (unsigned)qscale * quant_matrix[j]) >> 3;
level = (level - 1) | 1;
}
}