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@niedermayer.cc>
(cherry picked from commit 01636a63d4)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2023-01-11 18:59:16 +01:00
parent f0ecc9b12f
commit 4abb9d14b9
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@ -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
) {