[NETNS]: Udp sockets per-net lookup.

Add the net parameter to udp_get_port family of calls and
udp_lookup one and use it to filter sockets.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/udp.c

@@ -130,14 +130,14 @@ EXPORT_SYMBOL(sysctl_udp_wmem_min);
 atomic_t udp_memory_allocated;
 EXPORT_SYMBOL(udp_memory_allocated);
 
-static inline int __udp_lib_lport_inuse(__u16 num,
+static inline int __udp_lib_lport_inuse(struct net *net, __u16 num,
 					const struct hlist_head udptable[])
 {
 	struct sock *sk;
 	struct hlist_node *node;
 
 	sk_for_each(sk, node, &udptable[num & (UDP_HTABLE_SIZE - 1)])
-		if (sk->sk_hash == num)
+		if (sk->sk_net == net && sk->sk_hash == num)
 			return 1;
 	return 0;
 }
@@ -159,6 +159,7 @@ int __udp_lib_get_port(struct sock *sk, unsigned short snum,
 	struct hlist_head *head;
 	struct sock *sk2;
 	int    error = 1;
+	struct net *net = sk->sk_net;
 
 	write_lock_bh(&udp_hash_lock);
 
@@ -198,7 +199,7 @@ int __udp_lib_get_port(struct sock *sk, unsigned short snum,
 		/* 2nd pass: find hole in shortest hash chain */
 		rover = best;
 		for (i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; i++) {
-			if (! __udp_lib_lport_inuse(rover, udptable))
+			if (! __udp_lib_lport_inuse(net, rover, udptable))
 				goto gotit;
 			rover += UDP_HTABLE_SIZE;
 			if (rover > high)
@@ -218,6 +219,7 @@ int __udp_lib_get_port(struct sock *sk, unsigned short snum,
 		sk_for_each(sk2, node, head)
 			if (sk2->sk_hash == snum                             &&
 			    sk2 != sk                                        &&
+			    sk2->sk_net == net				     &&
 			    (!sk2->sk_reuse        || !sk->sk_reuse)         &&
 			    (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if
 			     || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
@@ -261,8 +263,8 @@ static inline int udp_v4_get_port(struct sock *sk, unsigned short snum)
 /* UDP is nearly always wildcards out the wazoo, it makes no sense to try
  * harder than this. -DaveM
  */
-static struct sock *__udp4_lib_lookup(__be32 saddr, __be16 sport,
-				      __be32 daddr, __be16 dport,
+static struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
+		__be16 sport, __be32 daddr, __be16 dport,
 		int dif, struct hlist_head udptable[])
 {
 	struct sock *sk, *result = NULL;
@@ -274,7 +276,8 @@ static struct sock *__udp4_lib_lookup(__be32 saddr, __be16 sport,
 	sk_for_each(sk, node, &udptable[hnum & (UDP_HTABLE_SIZE - 1)]) {
 		struct inet_sock *inet = inet_sk(sk);
 
-		if (sk->sk_hash == hnum && !ipv6_only_sock(sk)) {
+		if (sk->sk_net == net && sk->sk_hash == hnum &&
+				!ipv6_only_sock(sk)) {
 			int score = (sk->sk_family == PF_INET ? 1 : 0);
 			if (inet->rcv_saddr) {
 				if (inet->rcv_saddr != daddr)
@@ -361,8 +364,8 @@ void __udp4_lib_err(struct sk_buff *skb, u32 info, struct hlist_head udptable[])
 	int harderr;
 	int err;
 
-	sk = __udp4_lib_lookup(iph->daddr, uh->dest, iph->saddr, uh->source,
-			       skb->dev->ifindex, udptable		    );
+	sk = __udp4_lib_lookup(skb->dev->nd_net, iph->daddr, uh->dest,
+			iph->saddr, uh->source, skb->dev->ifindex, udptable);
 	if (sk == NULL) {
 		ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
 		return;	/* No socket for error */
@@ -1185,8 +1188,8 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct hlist_head udptable[],
 	if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
 		return __udp4_lib_mcast_deliver(skb, uh, saddr, daddr, udptable);
 
-	sk = __udp4_lib_lookup(saddr, uh->source, daddr, uh->dest,
-			       inet_iif(skb), udptable);
+	sk = __udp4_lib_lookup(skb->dev->nd_net, saddr, uh->source, daddr,
+			uh->dest, inet_iif(skb), udptable);
 
 	if (sk != NULL) {
 		int ret = 0;

net/ipv6/udp.c

@@ -56,7 +56,8 @@ static inline int udp_v6_get_port(struct sock *sk, unsigned short snum)
 	return udp_get_port(sk, snum, ipv6_rcv_saddr_equal);
 }
 
-static struct sock *__udp6_lib_lookup(struct in6_addr *saddr, __be16 sport,
+static struct sock *__udp6_lib_lookup(struct net *net,
+				      struct in6_addr *saddr, __be16 sport,
 				      struct in6_addr *daddr, __be16 dport,
 				      int dif, struct hlist_head udptable[])
 {
@@ -69,7 +70,8 @@ static struct sock *__udp6_lib_lookup(struct in6_addr *saddr, __be16 sport,
 	sk_for_each(sk, node, &udptable[hnum & (UDP_HTABLE_SIZE - 1)]) {
 		struct inet_sock *inet = inet_sk(sk);
 
-		if (sk->sk_hash == hnum && sk->sk_family == PF_INET6) {
+		if (sk->sk_net == net && sk->sk_hash == hnum &&
+				sk->sk_family == PF_INET6) {
 			struct ipv6_pinfo *np = inet6_sk(sk);
 			int score = 0;
 			if (inet->dport) {
@@ -233,7 +235,7 @@ void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 	struct sock *sk;
 	int err;
 
-	sk = __udp6_lib_lookup(daddr, uh->dest,
+	sk = __udp6_lib_lookup(skb->dev->nd_net, daddr, uh->dest,
 			       saddr, uh->source, inet6_iif(skb), udptable);
 	if (sk == NULL)
 		return;
@@ -478,7 +480,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct hlist_head udptable[],
 	 * check socket cache ... must talk to Alan about his plans
 	 * for sock caches... i'll skip this for now.
 	 */
-	sk = __udp6_lib_lookup(saddr, uh->source,
+	sk = __udp6_lib_lookup(skb->dev->nd_net, saddr, uh->source,
 			       daddr, uh->dest, inet6_iif(skb), udptable);
 
 	if (sk == NULL) {