From: Martin Josefsson <gandalf@wlug.westbo.se>
Date: Thu, 4 Jan 2007 20:16:54 +0000 (-0800)
Subject: [NETFILTER]: nf_nat: fix MASQUERADE crash on device down
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=bbdc176a2f39913063aaaf95bc27e4b18fd14953;p=deliverable%2Flinux.git

[NETFILTER]: nf_nat: fix MASQUERADE crash on device down

Check the return value of nfct_nat() in device_cmp(), we might very well
have non NAT conntrack entries as well (Netfilter bugzilla #528).

Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv4/netfilter/ipt_MASQUERADE.c b/net/ipv4/netfilter/ipt_MASQUERADE.c
index 28b9233956b5..d669685afd04 100644
--- a/net/ipv4/netfilter/ipt_MASQUERADE.c
+++ b/net/ipv4/netfilter/ipt_MASQUERADE.c
@@ -127,10 +127,13 @@ masquerade_target(struct sk_buff **pskb,
 static inline int
 device_cmp(struct ip_conntrack *i, void *ifindex)
 {
+	int ret;
 #ifdef CONFIG_NF_NAT_NEEDED
 	struct nf_conn_nat *nat = nfct_nat(i);
+
+	if (!nat)
+		return 0;
 #endif
-	int ret;
 
 	read_lock_bh(&masq_lock);
 #ifdef CONFIG_NF_NAT_NEEDED