From c722a69253a280b86b1d2a4ca00c89345a796781 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 10 Sep 2019 17:39:45 +0200 Subject: [PATCH] avcodec/vc1_block: Fix invalid shift with rangeredfrm Fixes: left shift of negative value -7 Fixes: 16959/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV3_fuzzer-5200360825683968 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/vc1_block.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/vc1_block.c b/libavcodec/vc1_block.c index 514206f6d2..fe7dbf8b1d 100644 --- a/libavcodec/vc1_block.c +++ b/libavcodec/vc1_block.c @@ -1997,7 +1997,7 @@ static int vc1_decode_b_mb(VC1Context *v) v->vc1dsp.vc1_inv_trans_8x8(s->block[i]); if (v->rangeredfrm) for (j = 0; j < 64; j++) - s->block[i][j] <<= 1; + s->block[i][j] *= 2; s->idsp.put_signed_pixels_clamped(s->block[i], s->dest[dst_idx] + off, i & 4 ? s->uvlinesize