[FFmpeg-devel] [PATCH 1/3] avcodec/vc1_block: Fix invalid shift with rangeredfrm
Michael Niedermayer
michael at niedermayer.cc
Wed Sep 11 03:18:41 EEST 2019
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 <michael at niedermayer.cc>
---
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
--
2.23.0
More information about the ffmpeg-devel
mailing list