From 47f4e2d8960ca756ca153ab8e3e93d80449b8c91 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 29 Jun 2015 21:08:05 +0200 Subject: [PATCH] avcodec/pngdec: Only allow one IHDR chunk Multiple IHDR chunks are forbidden in PNG Fixes inconsistency and out of array accesses Fixes: asan_heap-oob_4d5c5a_1738_cov_2638287726_c-m2-8f2b481b7fd9bd745e620b7c01a18df2.png Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind Signed-off-by: Michael Niedermayer --- libavcodec/pngdec.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c index ceda383209..f8b398ffde 100644 --- a/libavcodec/pngdec.c +++ b/libavcodec/pngdec.c @@ -542,6 +542,11 @@ static int decode_ihdr_chunk(AVCodecContext *avctx, PNGDecContext *s, return AVERROR_INVALIDDATA; } + if (s->state & PNG_IHDR) { + av_log(avctx, AV_LOG_ERROR, "Multiple IHDR\n"); + return AVERROR_INVALIDDATA; + } + s->width = bytestream2_get_be32(&s->gb); s->height = bytestream2_get_be32(&s->gb); if (av_image_check_size(s->width, s->height, 0, avctx)) {