From f8a0e9f9f71cf5650bdc250ff7475e0f7d8e8420 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 22 Feb 2020 00:42:30 +0100 Subject: 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 Signed-off-by: Michael Niedermayer --- libavcodec/magicyuv.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/libavcodec/magicyuv.c b/libavcodec/magicyuv.c index 21a32785bc..aacd0d4d7d 100644 --- a/libavcodec/magicyuv.c +++ b/libavcodec/magicyuv.c @@ -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]) -- cgit v1.2.1