[NETNS]: Make bind buckets live in net namespaces.

This tags the inet_bind_bucket struct with net pointer,
initializes it during creation and makes a filtering
during lookup.

A better hashfn, that takes the net into account is to
be done in the future, but currently all bind buckets
with similar port will be in one hash chain.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/inet_hashtables.h

@@ -74,6 +74,7 @@ struct inet_ehash_bucket {
  * ports are created in O(1) time?  I thought so. ;-)	-DaveM
  */
 struct inet_bind_bucket {
+	struct net		*ib_net;
 	unsigned short		port;
 	signed short		fastreuse;
 	struct hlist_node	node;
@@ -194,6 +195,7 @@ static inline void inet_ehash_locks_free(struct inet_hashinfo *hashinfo)
 
 extern struct inet_bind_bucket *
 		    inet_bind_bucket_create(struct kmem_cache *cachep,
+					    struct net *net,
 					    struct inet_bind_hashbucket *head,
 					    const unsigned short snum);
 extern void inet_bind_bucket_destroy(struct kmem_cache *cachep,

net/ipv4/inet_connection_sock.c

@@ -87,6 +87,7 @@ int inet_csk_get_port(struct inet_hashinfo *hashinfo,
 	struct hlist_node *node;
 	struct inet_bind_bucket *tb;
 	int ret;
+	struct net *net = sk->sk_net;
 
 	local_bh_disable();
 	if (!snum) {
@@ -100,7 +101,7 @@ int inet_csk_get_port(struct inet_hashinfo *hashinfo,
 			head = &hashinfo->bhash[inet_bhashfn(rover, hashinfo->bhash_size)];
 			spin_lock(&head->lock);
 			inet_bind_bucket_for_each(tb, node, &head->chain)
-				if (tb->port == rover)
+				if (tb->ib_net == net && tb->port == rover)
 					goto next;
 			break;
 		next:
@@ -127,7 +128,7 @@ int inet_csk_get_port(struct inet_hashinfo *hashinfo,
 		head = &hashinfo->bhash[inet_bhashfn(snum, hashinfo->bhash_size)];
 		spin_lock(&head->lock);
 		inet_bind_bucket_for_each(tb, node, &head->chain)
-			if (tb->port == snum)
+			if (tb->ib_net == net && tb->port == snum)
 				goto tb_found;
 	}
 	tb = NULL;
@@ -147,7 +148,8 @@ int inet_csk_get_port(struct inet_hashinfo *hashinfo,
 	}
 tb_not_found:
 	ret = 1;
-	if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep, head, snum)) == NULL)
+	if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
+					net, head, snum)) == NULL)
 		goto fail_unlock;
 	if (hlist_empty(&tb->owners)) {
 		if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)

net/ipv4/inet_hashtables.c

@@ -28,12 +28,14 @@
  * The bindhash mutex for snum's hash chain must be held here.
  */
 struct inet_bind_bucket *inet_bind_bucket_create(struct kmem_cache *cachep,
+						 struct net *net,
 						 struct inet_bind_hashbucket *head,
 						 const unsigned short snum)
 {
 	struct inet_bind_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC);
 
 	if (tb != NULL) {
+		tb->ib_net       = net;
 		tb->port      = snum;
 		tb->fastreuse = 0;
 		INIT_HLIST_HEAD(&tb->owners);
@@ -359,6 +361,7 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row,
 	struct inet_bind_hashbucket *head;
 	struct inet_bind_bucket *tb;
 	int ret;
+	struct net *net = sk->sk_net;
 
 	if (!snum) {
 		int i, remaining, low, high, port;
@@ -381,7 +384,7 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row,
 			 * unique enough.
 			 */
 			inet_bind_bucket_for_each(tb, node, &head->chain) {
-				if (tb->port == port) {
+				if (tb->ib_net == net && tb->port == port) {
 					BUG_TRAP(!hlist_empty(&tb->owners));
 					if (tb->fastreuse >= 0)
 						goto next_port;
@@ -392,7 +395,8 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row,
 				}
 			}
 
-			tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep, head, port);
+			tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
+					net, head, port);
 			if (!tb) {
 				spin_unlock(&head->lock);
 				break;