netfilter: Pass net into okfn

This is immediately motivated by the bridge code that chains functions that
call into netfilter.  Without passing net into the okfns the bridge code would
need to guess about the best expression for the network namespace to process
packets in.

As net is frequently one of the first things computed in continuation functions
after netfilter has done it's job passing in the desired network namespace is in
many cases a code simplification.

To support this change the function dst_output_okfn is introduced to
simplify passing dst_output as an okfn.  For the moment dst_output_okfn
just silently drops the struct net.

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

8 files changed, 14 insertions, 18 deletions

diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index ae71e9ade5f9..61ff5ea31283 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -621,7 +621,7 @@ out:
 }
 EXPORT_SYMBOL(arp_create);
 
-static int arp_xmit_finish(struct sock *sk, struct sk_buff *skb)
+static int arp_xmit_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	return dev_queue_xmit(skb);
 }
@@ -642,7 +642,7 @@ EXPORT_SYMBOL(arp_xmit);
  *	Process an arp request.
  */
 
-static int arp_process(struct sock *sk, struct sk_buff *skb)
+static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	struct net_device *dev = skb->dev;
 	struct in_device *in_dev = __in_dev_get_rcu(dev);
@@ -654,7 +654,6 @@ static int arp_process(struct sock *sk, struct sk_buff *skb)
 	u16 dev_type = dev->type;
 	int addr_type;
 	struct neighbour *n;
-	struct net *net = dev_net(dev);
 	bool is_garp = false;
 
 	/* arp_rcv below verifies the ARP header and verifies the device
@@ -865,7 +864,7 @@ out:
 
 static void parp_redo(struct sk_buff *skb)
 {
-	arp_process(NULL, skb);
+	arp_process(dev_net(skb->dev), NULL, skb);
 }
 
 
diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c
index 0a3c45a2e757..d66cfb35ba74 100644
--- a/net/ipv4/ip_forward.c
+++ b/net/ipv4/ip_forward.c
@@ -61,9 +61,8 @@ static bool ip_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
 }
 
 
-static int ip_forward_finish(struct sock *sk, struct sk_buff *skb)
+static int ip_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
-	struct net *net = dev_net(skb_dst(skb)->dev);
 	struct ip_options *opt	= &(IPCB(skb)->opt);
 
 	IP_INC_STATS_BH(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 991d082c7312..7cc9f7bb7fb7 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -188,10 +188,8 @@ bool ip_call_ra_chain(struct sk_buff *skb)
 	return false;
 }
 
-static int ip_local_deliver_finish(struct sock *sk, struct sk_buff *skb)
+static int ip_local_deliver_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
-	struct net *net = dev_net(skb->dev);
-
 	__skb_pull(skb, skb_network_header_len(skb));
 
 	rcu_read_lock();
@@ -311,10 +309,9 @@ drop:
 int sysctl_ip_early_demux __read_mostly = 1;
 EXPORT_SYMBOL(sysctl_ip_early_demux);
 
-static int ip_rcv_finish(struct sock *sk, struct sk_buff *skb)
+static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	const struct iphdr *iph = ip_hdr(skb);
-	struct net *net = dev_net(skb->dev);
 	struct rtable *rt;
 
 	if (sysctl_ip_early_demux && !skb_dst(skb) && !skb->sk) {
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 4c9532259a7f..09a6b7bb7ea3 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -104,7 +104,7 @@ static int __ip_local_out_sk(struct sock *sk, struct sk_buff *skb)
 	ip_send_check(iph);
 	return nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT,
 		       net, sk, skb, NULL, skb_dst(skb)->dev,
-		       dst_output);
+		       dst_output_okfn);
 }
 
 int __ip_local_out(struct sk_buff *skb)
@@ -266,7 +266,7 @@ static int ip_finish_output_gso(struct sock *sk, struct sk_buff *skb,
 	return ret;
 }
 
-static int ip_finish_output(struct sock *sk, struct sk_buff *skb)
+static int ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	unsigned int mtu;
 
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index a88c0c5374ff..cfcb996ec51b 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -1678,10 +1678,10 @@ static void ip_encap(struct net *net, struct sk_buff *skb,
 	nf_reset(skb);
 }
 
-static inline int ipmr_forward_finish(struct sock *sk, struct sk_buff *skb)
+static inline int ipmr_forward_finish(struct net *net, struct sock *sk,
+				      struct sk_buff *skb)
 {
 	struct ip_options *opt = &(IPCB(skb)->opt);
-	struct net *net = dev_net(skb_dst(skb)->dev);
 
 	IP_INC_STATS_BH(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
 	IP_ADD_STATS_BH(net, IPSTATS_MIB_OUTOCTETS, skb->len);
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 2045b1aaa6ef..28ef8a913130 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -413,7 +413,7 @@ static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
 
 	err = NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_OUT,
 		      net, sk, skb, NULL, rt->dst.dev,
-		      dst_output);
+		      dst_output_okfn);
 	if (err > 0)
 		err = net_xmit_errno(err);
 	if (err)
diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index 5093000d3d5e..62e1e72db461 100644
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -22,7 +22,8 @@ int xfrm4_extract_input(struct xfrm_state *x, struct sk_buff *skb)
 	return xfrm4_extract_header(skb);
 }
 
-static inline int xfrm4_rcv_encap_finish(struct sock *sk, struct sk_buff *skb)
+static inline int xfrm4_rcv_encap_finish(struct net *net, struct sock *sk,
+					 struct sk_buff *skb)
 {
 	if (!skb_dst(skb)) {
 		const struct iphdr *iph = ip_hdr(skb);
diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c
index e4a85199e015..28ae2048b93a 100644
--- a/net/ipv4/xfrm4_output.c
+++ b/net/ipv4/xfrm4_output.c
@@ -80,7 +80,7 @@ int xfrm4_output_finish(struct sock *sk, struct sk_buff *skb)
 	return xfrm_output(sk, skb);
 }
 
-static int __xfrm4_output(struct sock *sk, struct sk_buff *skb)
+static int __xfrm4_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	struct xfrm_state *x = skb_dst(skb)->xfrm;