From 9bcb8caac3bd109cee70a98560181a551c6317a7 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 26 Mar 2023 22:35:50 +0200 Subject: [PATCH] avcodec/vp3: Check width to avoid assertion failure Fixes: Assertion failure on x86-32 av_assert2(block_w * sizeof(pixel) <= FFABS(buf_linesize)); in ff_emulated_edge_mc() Fixes: 39641/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_THEORA_fuzzer-5925660741206016 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit dab1cd2dc0471d497f481736059b2023c5b7986a) Signed-off-by: Michael Niedermayer --- libavcodec/vp3.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c index 2933544256..f8ec20196d 100644 --- a/libavcodec/vp3.c +++ b/libavcodec/vp3.c @@ -1747,6 +1747,8 @@ static av_cold int vp3_decode_init(AVCodecContext *avctx) s->avctx = avctx; s->width = FFALIGN(avctx->coded_width, 16); s->height = FFALIGN(avctx->coded_height, 16); + if (s->width < 18) + return AVERROR_PATCHWELCOME; if (avctx->codec_id != AV_CODEC_ID_THEORA) avctx->pix_fmt = AV_PIX_FMT_YUV420P; avctx->chroma_sample_location = AVCHROMA_LOC_CENTER; @@ -2307,7 +2309,9 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb) /* sanity check */ if (av_image_check_size(visible_width, visible_height, 0, avctx) < 0 || visible_width + offset_x > s->width || - visible_height + offset_y > s->height) { + visible_height + offset_y > s->height || + visible_width < 18 + ) { av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions - w:%d h:%d x:%d y:%d (%dx%d).\n", visible_width, visible_height, offset_x, offset_y, @@ -2353,6 +2357,8 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb) } else avctx->pix_fmt = AV_PIX_FMT_YUV420P; + if (s->width < 18) + return AVERROR_PATCHWELCOME; ret = ff_set_dimensions(avctx, s->width, s->height); if (ret < 0) return ret;