avcodec/magicyuv: Check that there are enough lines for interlacing to be possible

Fixes: out of array access
Fixes: 20763/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MAGICYUV_fuzzer-5759562508664832

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-02-22 00:42:30 +01:00
parent 618a9bea65
commit f8a0e9f9f7

View File

@ -659,6 +659,17 @@ static int magy_decode_frame(AVCodecContext *avctx, void *data,
return AVERROR_INVALIDDATA;
}
if (s->interlaced) {
if ((s->slice_height >> s->vshift[1]) < 2) {
av_log(avctx, AV_LOG_ERROR, "impossible slice height\n");
return AVERROR_INVALIDDATA;
}
if ((avctx->coded_height % s->slice_height) && ((avctx->coded_height % s->slice_height) >> s->vshift[1]) < 2) {
av_log(avctx, AV_LOG_ERROR, "impossible height\n");
return AVERROR_INVALIDDATA;
}
}
for (i = 0; i < s->planes; i++) {
av_fast_malloc(&s->slices[i], &s->slices_size[i], s->nb_slices * sizeof(Slice));
if (!s->slices[i])