From 083edca05ab1fa6efac1ba414018f7f45a4a83ff Mon Sep 17 00:00:00 2001
From: Patrick McHardy <kaber@trash.net>
Date: Mon, 24 Jul 2006 22:52:10 -0700
Subject: [PATCH] [NETFILTER]: H.323 helper: fix possible NULL-ptr dereference

An RCF message containing a timeout results in a NULL-ptr dereference if
no RRQ has been seen before.

Noticed by the "SATURN tool", reported by Thomas Dillig <tdillig@stanford.edu>
and Isil Dillig <isil@stanford.edu>.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/ipv4/netfilter/ip_conntrack_helper_h323.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/netfilter/ip_conntrack_helper_h323.c b/net/ipv4/netfilter/ip_conntrack_helper_h323.c
index af35235672d5..9a39e2969712 100644
--- a/net/ipv4/netfilter/ip_conntrack_helper_h323.c
+++ b/net/ipv4/netfilter/ip_conntrack_helper_h323.c
@@ -1200,7 +1200,7 @@ static struct ip_conntrack_expect *find_expect(struct ip_conntrack *ct,
 	tuple.dst.protonum = IPPROTO_TCP;
 
 	exp = __ip_conntrack_expect_find(&tuple);
-	if (exp->master == ct)
+	if (exp && exp->master == ct)
 		return exp;
 	return NULL;
 }
-- 
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