inet: toss struct net initialization around

Some places, that deal with ICMP statistics already have where
to get a struct net from, but use it directly, without declaring
a separate variable on the stack.

Since I will need this net soon, I declare a struct net on the
stack and use it in the existing places in a separate patch not
to spoil the future ones.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/dccp/ipv4.c

@@ -205,13 +205,14 @@ static void dccp_v4_err(struct sk_buff *skb, u32 info)
 	struct sock *sk;
 	__u64 seq;
 	int err;
+	struct net *net = dev_net(skb->dev);
 
 	if (skb->len < (iph->ihl << 2) + 8) {
 		ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
 		return;
 	}
 
-	sk = inet_lookup(dev_net(skb->dev), &dccp_hashinfo,
+	sk = inet_lookup(net, &dccp_hashinfo,
 			iph->daddr, dh->dccph_dport,
 			iph->saddr, dh->dccph_sport, inet_iif(skb));
 	if (sk == NULL) {

net/ipv4/icmp.c

@@ -973,6 +973,7 @@ int icmp_rcv(struct sk_buff *skb)
 {
 	struct icmphdr *icmph;
 	struct rtable *rt = skb->rtable;
+	struct net *net = dev_net(rt->u.dst.dev);
 
 	if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 		int nh;
@@ -1027,9 +1028,6 @@ int icmp_rcv(struct sk_buff *skb)
 	 */
 
 	if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
-		struct net *net;
-
-		net = dev_net(rt->u.dst.dev);
 		/*
 		 *	RFC 1122: 3.2.2.6 An ICMP_ECHO to broadcast MAY be
 		 *	  silently ignored (we let user decide with a sysctl).

net/ipv4/tcp_ipv4.c

@@ -343,13 +343,14 @@ void tcp_v4_err(struct sk_buff *skb, u32 info)
 	struct sock *sk;
 	__u32 seq;
 	int err;
+	struct net *net = dev_net(skb->dev);
 
 	if (skb->len < (iph->ihl << 2) + 8) {
 		ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
 		return;
 	}
 
-	sk = inet_lookup(dev_net(skb->dev), &tcp_hashinfo, iph->daddr, th->dest,
+	sk = inet_lookup(net, &tcp_hashinfo, iph->daddr, th->dest,
 			iph->saddr, th->source, inet_iif(skb));
 	if (!sk) {
 		ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);

net/ipv4/udp.c

@@ -354,8 +354,9 @@ void __udp4_lib_err(struct sk_buff *skb, u32 info, struct hlist_head udptable[])
 	struct sock *sk;
 	int harderr;
 	int err;
+	struct net *net = dev_net(skb->dev);
 
-	sk = __udp4_lib_lookup(dev_net(skb->dev), iph->daddr, uh->dest,
+	sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,
 			iph->saddr, uh->source, skb->dev->ifindex, udptable);
 	if (sk == NULL) {
 		ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);