[FFmpeg-cvslog] avcodec/utils: allocate a line more for VC1 and WMV3

[Michael Niedermayer]

ffmpeg | branch: release/4.3 | Michael Niedermayer <michael at niedermayer.cc> | Wed Jan 11 18:59:16 2023 +0100| [4abb9d14b9a9fc2bdd4181ea29ed230619751eea] | committer: Michael Niedermayer

avcodec/utils: allocate a line more for VC1 and WMV3

Fixes: out of array read on 32bit
Fixes: 54857/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VC1_fuzzer-5840588224462848

The chroma MC code reads over the currently allocated frame.
Alternative fixes would be allocating a few bytes more at the end instead of a whole
line extra or to adjust the threshold where the edge emu code is activated

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 01636a63d452c592ece35af6f72bb7affcad58f2)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=4abb9d14b9a9fc2bdd4181ea29ed230619751eea
---

 libavcodec/utils.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 9054c6c9a0..5ead2f59a6 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -329,6 +329,7 @@ void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
     *width  = FFALIGN(*width, w_align);
     *height = FFALIGN(*height, h_align);
     if (s->codec_id == AV_CODEC_ID_H264 || s->lowres ||
+        s->codec_id == AV_CODEC_ID_VC1  || s->codec_id == AV_CODEC_ID_WMV3 ||
         s->codec_id == AV_CODEC_ID_VP5  || s->codec_id == AV_CODEC_ID_VP6 ||
         s->codec_id == AV_CODEC_ID_VP6F || s->codec_id == AV_CODEC_ID_VP6A
     ) {