From d2aff350bc8250d1efe04e90822f49f4b8aea9ae Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 20 Feb 2020 18:51:36 +0100 Subject: [PATCH] avcodec/cdtoons: Fix off by 4 check on diff_size Fixes: out of array read Fixes: 20742/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_CDTOONS_fuzzer-5738148607033344 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/cdtoons.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/cdtoons.c b/libavcodec/cdtoons.c index dc4fa6bf0b..d5dce6351f 100644 --- a/libavcodec/cdtoons.c +++ b/libavcodec/cdtoons.c @@ -269,7 +269,7 @@ static int cdtoons_decode_frame(AVCodecContext *avctx, void *data, diff_size = bytestream_get_be32(&buf); width = bytestream_get_be16(&buf); height = bytestream_get_be16(&buf); - if (diff_size < 4 || diff_size - 4 > eod - buf) { + if (diff_size < 8 || diff_size - 4 > eod - buf) { av_log(avctx, AV_LOG_WARNING, "Ran (seriously) out of data for Diff frame data.\n"); return AVERROR_INVALIDDATA; }