From c64180fac8442d4b0f1ed9cb07265361c193400e Mon Sep 17 00:00:00 2001 From: Anton Khirnov Date: Fri, 2 Apr 2021 16:00:23 +0200 Subject: [PATCH] lavc/pngdec: improve chunk length check The length does not cover the chunk type or CRC. (cherry picked from commit ae08eec6a1f2129cd231a0ab664f0f17b854d138) Signed-off-by: Anton Khirnov --- libavcodec/pngdec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c index f3295688c6..0ff81d740c 100644 --- a/libavcodec/pngdec.c +++ b/libavcodec/pngdec.c @@ -1217,7 +1217,7 @@ static int decode_frame_common(AVCodecContext *avctx, PNGDecContext *s, } length = bytestream2_get_be32(&s->gb); - if (length > 0x7fffffff || length > bytestream2_get_bytes_left(&s->gb)) { + if (length > 0x7fffffff || length + 8 > bytestream2_get_bytes_left(&s->gb)) { av_log(avctx, AV_LOG_ERROR, "chunk too big\n"); ret = AVERROR_INVALIDDATA; goto fail;