2 files changed, 32 insertions, 38 deletions

diff --git a/net/l2tp/l2tp_ip.c b/net/l2tp/l2tp_ip.c
index 4d1c942cc91b..b517c3366922 100644
--- a/net/l2tp/l2tp_ip.c
+++ b/net/l2tp/l2tp_ip.c
@@ -257,15 +257,9 @@ static int l2tp_ip_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (addr->l2tp_family != AF_INET)
 		return -EINVAL;
 
-	ret = -EADDRINUSE;
-	read_lock_bh(&l2tp_ip_lock);
-	if (__l2tp_ip_bind_lookup(net, addr->l2tp_addr.s_addr,
-				  sk->sk_bound_dev_if, addr->l2tp_conn_id))
-		goto out_in_use;
-
-	read_unlock_bh(&l2tp_ip_lock);
-
 	lock_sock(sk);
+
+	ret = -EINVAL;
 	if (!sock_flag(sk, SOCK_ZAPPED))
 		goto out;
 
@@ -282,14 +276,22 @@ static int l2tp_ip_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 		inet->inet_rcv_saddr = inet->inet_saddr = addr->l2tp_addr.s_addr;
 	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
 		inet->inet_saddr = 0;  /* Use device */
-	sk_dst_reset(sk);
 
+	write_lock_bh(&l2tp_ip_lock);
+	if (__l2tp_ip_bind_lookup(net, addr->l2tp_addr.s_addr,
+				  sk->sk_bound_dev_if, addr->l2tp_conn_id)) {
+		write_unlock_bh(&l2tp_ip_lock);
+		ret = -EADDRINUSE;
+		goto out;
+	}
+
+	sk_dst_reset(sk);
 	l2tp_ip_sk(sk)->conn_id = addr->l2tp_conn_id;
 
-	write_lock_bh(&l2tp_ip_lock);
 	sk_add_bind_node(sk, &l2tp_ip_bind_table);
 	sk_del_node_init(sk);
 	write_unlock_bh(&l2tp_ip_lock);
+
 	ret = 0;
 	sock_reset_flag(sk, SOCK_ZAPPED);
 
@@ -297,11 +299,6 @@ out:
 	release_sock(sk);
 
 	return ret;
-
-out_in_use:
-	read_unlock_bh(&l2tp_ip_lock);
-
-	return ret;
 }
 
 static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index e3fc7786f188..5f2ae615c5f9 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -267,6 +267,7 @@ static int l2tp_ip6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	struct sockaddr_l2tpip6 *addr = (struct sockaddr_l2tpip6 *) uaddr;
 	struct net *net = sock_net(sk);
 	__be32 v4addr = 0;
+	int bound_dev_if;
 	int addr_type;
 	int err;
 
@@ -285,13 +286,6 @@ static int l2tp_ip6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (addr_type & IPV6_ADDR_MULTICAST)
 		return -EADDRNOTAVAIL;
 
-	err = -EADDRINUSE;
-	read_lock_bh(&l2tp_ip6_lock);
-	if (__l2tp_ip6_bind_lookup(net, &addr->l2tp_addr,
-				   sk->sk_bound_dev_if, addr->l2tp_conn_id))
-		goto out_in_use;
-	read_unlock_bh(&l2tp_ip6_lock);
-
 	lock_sock(sk);
 
 	err = -EINVAL;
@@ -301,28 +295,25 @@ static int l2tp_ip6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (sk->sk_state != TCP_CLOSE)
 		goto out_unlock;
 
+	bound_dev_if = sk->sk_bound_dev_if;
+
 	/* Check if the address belongs to the host. */
 	rcu_read_lock();
 	if (addr_type != IPV6_ADDR_ANY) {
 		struct net_device *dev = NULL;
 
 		if (addr_type & IPV6_ADDR_LINKLOCAL) {
-			if (addr_len >= sizeof(struct sockaddr_in6) &&
-			    addr->l2tp_scope_id) {
-				/* Override any existing binding, if another
-				 * one is supplied by user.
-				 */
-				sk->sk_bound_dev_if = addr->l2tp_scope_id;
-			}
+			if (addr->l2tp_scope_id)
+				bound_dev_if = addr->l2tp_scope_id;
 
 			/* Binding to link-local address requires an
-			   interface */
-			if (!sk->sk_bound_dev_if)
+			 * interface.
+			 */
+			if (!bound_dev_if)
 				goto out_unlock_rcu;
 
 			err = -ENODEV;
-			dev = dev_get_by_index_rcu(sock_net(sk),
-						   sk->sk_bound_dev_if);
+			dev = dev_get_by_index_rcu(sock_net(sk), bound_dev_if);
 			if (!dev)
 				goto out_unlock_rcu;
 		}
@@ -337,13 +328,22 @@ static int l2tp_ip6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	}
 	rcu_read_unlock();
 
-	inet->inet_rcv_saddr = inet->inet_saddr = v4addr;
+	write_lock_bh(&l2tp_ip6_lock);
+	if (__l2tp_ip6_bind_lookup(net, &addr->l2tp_addr, bound_dev_if,
+				   addr->l2tp_conn_id)) {
+		write_unlock_bh(&l2tp_ip6_lock);
+		err = -EADDRINUSE;
+		goto out_unlock;
+	}
+
+	inet->inet_saddr = v4addr;
+	inet->inet_rcv_saddr = v4addr;
+	sk->sk_bound_dev_if = bound_dev_if;
 	sk->sk_v6_rcv_saddr = addr->l2tp_addr;
 	np->saddr = addr->l2tp_addr;
 
 	l2tp_ip6_sk(sk)->conn_id = addr->l2tp_conn_id;
 
-	write_lock_bh(&l2tp_ip6_lock);
 	sk_add_bind_node(sk, &l2tp_ip6_bind_table);
 	sk_del_node_init(sk);
 	write_unlock_bh(&l2tp_ip6_lock);
@@ -356,10 +356,7 @@ out_unlock_rcu:
 	rcu_read_unlock();
 out_unlock:
 	release_sock(sk);
-	return err;
 
-out_in_use:
-	read_unlock_bh(&l2tp_ip6_lock);
 	return err;
 }