From 29c7a02bb2858e669441c642af3230db5f147f50 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 2 Jul 2018 19:11:46 +0200 Subject: [PATCH] avcodec/shorten: Fix undefined addition in shorten_decode_frame() Fixes: signed integer overflow: 1139785606 + 1454196085 cannot be represented in type 'int' Fixes: 8937/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SHORTEN_fuzzer-6202943597445120 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 3b10bb8772c76177cc47b8d15a6970f19dd11039) Signed-off-by: Michael Niedermayer --- libavcodec/shorten.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/shorten.c b/libavcodec/shorten.c index cbd8a78bc4..f481a84fed 100644 --- a/libavcodec/shorten.c +++ b/libavcodec/shorten.c @@ -575,7 +575,7 @@ static int shorten_decode_frame(AVCodecContext *avctx, void *data, else { int32_t sum = (s->version < 2) ? 0 : s->nmean / 2; for (i = 0; i < s->nmean; i++) - sum += s->offset[channel][i]; + sum += (unsigned)s->offset[channel][i]; coffset = sum / s->nmean; if (s->version >= 2) coffset = s->bitshift == 0 ? coffset : coffset >> s->bitshift - 1 >> 1;