From 9d1c47ec033d038e04578eaf0767c8983250d03d Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 23 Apr 2021 19:44:08 +0200 Subject: [PATCH] avformat/dsicin: Check packet size for overflow Fixes: signed integer overflow: 24672 + 2147483424 cannot be represented in type 'int' Fixes: 29102/clusterfuzz-testcase-minimized-ffmpeg_dem_DSICIN_fuzzer-6731325979623424 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavformat/dsicin.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/libavformat/dsicin.c b/libavformat/dsicin.c index 5693b11e8c..481f365a53 100644 --- a/libavformat/dsicin.c +++ b/libavformat/dsicin.c @@ -166,7 +166,8 @@ static int cin_read_packet(AVFormatContext *s, AVPacket *pkt) CinDemuxContext *cin = s->priv_data; AVIOContext *pb = s->pb; CinFrameHeader *hdr = &cin->frame_header; - int rc, palette_type, pkt_size; + int rc, palette_type; + int64_t pkt_size; int ret; if (cin->audio_buffer_size == 0) { @@ -182,7 +183,9 @@ static int cin_read_packet(AVFormatContext *s, AVPacket *pkt) } /* palette and video packet */ - pkt_size = (palette_type + 3) * hdr->pal_colors_count + hdr->video_frame_size; + pkt_size = (palette_type + 3LL) * hdr->pal_colors_count + hdr->video_frame_size; + if (pkt_size + 4 > INT_MAX) + return AVERROR_INVALIDDATA; pkt_size = ffio_limit(pb, pkt_size);