From 22f743e60201c3cc70dde007e69b03f0e35d267a Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 20 Aug 2018 20:15:19 +0200 Subject: [PATCH] avcodec/snowdec: Fix integer overflow with motion vector residual Fixes: signed integer overflow: -19818 + -2147483648 cannot be represented in type 'int' Fixes: 9545/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SNOW_fuzzer-4928769537081344 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit acba153a148782c08f9fd17f0c05b93468f3cbd0) Signed-off-by: Michael Niedermayer --- libavcodec/snowdec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/snowdec.c b/libavcodec/snowdec.c index 00fa064102..a9fe91d251 100644 --- a/libavcodec/snowdec.c +++ b/libavcodec/snowdec.c @@ -208,8 +208,8 @@ static int decode_q_branch(SnowContext *s, int level, int x, int y){ return AVERROR_INVALIDDATA; } pred_mv(s, &mx, &my, ref, left, top, tr); - mx+= get_symbol(&s->c, &s->block_state[128 + 32*(mx_context + 16*!!ref)], 1); - my+= get_symbol(&s->c, &s->block_state[128 + 32*(my_context + 16*!!ref)], 1); + mx+= (unsigned)get_symbol(&s->c, &s->block_state[128 + 32*(mx_context + 16*!!ref)], 1); + my+= (unsigned)get_symbol(&s->c, &s->block_state[128 + 32*(my_context + 16*!!ref)], 1); } set_blocks(s, level, x, y, l, cb, cr, mx, my, ref, type); }else{