From 70432eac0b511105a5d6654cb794bc5f3e983ee0 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 22 Jul 2019 00:03:15 +0200 Subject: [PATCH] avcodec/pngdec: consider chunk size in minimal size check assuming each block contains an empty chunk there has to be at least 8 bytes extra. Fixes: 15327/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_LSCR_fuzzer-5676669303521280 Fixes: Timeout (11->5sec) Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/pngdec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c index bf5a5191cc..cad5796545 100644 --- a/libavcodec/pngdec.c +++ b/libavcodec/pngdec.c @@ -1547,7 +1547,7 @@ static int decode_frame_lscr(AVCodecContext *avctx, return ret; nb_blocks = bytestream2_get_le16(gb); - if (bytestream2_get_bytes_left(gb) < 2 + nb_blocks * 12) + if (bytestream2_get_bytes_left(gb) < 2 + nb_blocks * (12 + 8)) return AVERROR_INVALIDDATA; if (s->last_picture.f->data[0]) {