From d719981273bc779c7d1e879d88404fd867f93a0e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Storsj=C3=B6?= <martin@martin.st>
Date: Tue, 3 Sep 2013 13:53:23 +0300
Subject: [PATCH] 4xm: Check that the read track value is non-negative
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
Signed-off-by: Martin Storsjö <martin@martin.st>
---
 libavformat/4xm.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavformat/4xm.c b/libavformat/4xm.c
index f003c9c25a..7a87c3695a 100644
--- a/libavformat/4xm.c
+++ b/libavformat/4xm.c
@@ -131,6 +131,8 @@ static int parse_strk(AVFormatContext *s,
         return AVERROR_INVALIDDATA;
 
     track = AV_RL32(buf + 8);
+    if (track < 0)
+        return AVERROR_INVALIDDATA;
     if (track + 1 > fourxm->track_count) {
         if (av_reallocp_array(&fourxm->tracks, track + 1, sizeof(AudioTrack)))
             return AVERROR(ENOMEM);