ipv4: Compute net once in ip_forward

Compute struct net from the input device in ip_forward before it is
used.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c
index 28fb901..ba2f66b 100644 (file)
--- a/net/ipv4/ip_forward.c
+++ b/net/ipv4/ip_forward.c
@@ -81,6 +81,7 @@ int ip_forward(struct sk_buff *skb)
        struct iphdr *iph;      /* Our header */
        struct rtable *rt;      /* Route we use */
        struct ip_options *opt  = &(IPCB(skb)->opt);
+       struct net *net;
 
        /* that should never happen */
        if (skb->pkt_type != PACKET_HOST)
@@ -99,6 +100,7 @@ int ip_forward(struct sk_buff *skb)
                return NET_RX_SUCCESS;
 
        skb_forward_csum(skb);
+       net = dev_net(skb->dev);
 
        /*
         *      According to the RFC, we must first decrease the TTL field. If
@@ -119,7 +121,7 @@ int ip_forward(struct sk_buff *skb)
        IPCB(skb)->flags |= IPSKB_FORWARDED;
        mtu = ip_dst_mtu_maybe_forward(&rt->dst, true);
        if (ip_exceeds_mtu(skb, mtu)) {
-               IP_INC_STATS(dev_net(rt->dst.dev), IPSTATS_MIB_FRAGFAILS);
+               IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
                icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
                          htonl(mtu));
                goto drop;
@@ -155,7 +157,7 @@ sr_failed:
 
 too_many_hops:
        /* Tell the sender its packet died... */
-       IP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_INHDRERRORS);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_INHDRERRORS);
        icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
 drop:
        kfree_skb(skb);