From: wm4 <nfxjfg@googlemail.com>
Date: Tue, 3 Feb 2015 18:04:12 +0000 (+0100)
Subject: avformat/mpc8: fix hang with fuzzed file
X-Git-Tag: archive/raspbian/6%11.12-1_deb8u8+rpi1^2~7
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=0c0c8e5ff3e93daea5ffef923404420343eda8c0;p=libav.git

avformat/mpc8: fix hang with fuzzed file

This can lead to an endless loop by seeking back a few bytes after each
attempted chunk read. Assuming negative sizes are always invalid, this
is easy to fix. Other code in this demuxer treats negative sizes as
invalid as well.

Fixes ticket #4262.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Gbp-Pq: Name CVE-2019-14442.patch
---

diff --git a/libavformat/mpc8.c b/libavformat/mpc8.c
index 3564e81..4b12219 100644
--- a/libavformat/mpc8.c
+++ b/libavformat/mpc8.c
@@ -216,6 +216,10 @@ static int mpc8_read_header(AVFormatContext *s)
     while(!pb->eof_reached){
         pos = avio_tell(pb);
         mpc8_get_chunk_header(pb, &tag, &size);
+        if (size < 0) {
+            av_log(s, AV_LOG_ERROR, "Invalid chunk length\n");
+            return AVERROR_INVALIDDATA;
+        }
         if(tag == TAG_STREAMHDR)
             break;
         mpc8_handle_chunk(s, tag, pos, size);