1 files changed, 117 insertions, 88 deletions

diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index a2c8747d2936..88b397c30d86 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -25,6 +25,7 @@
 #include <net/udp.h>
 #include <net/inet_common.h>
 #include <net/inet_hashtables.h>
+#include <net/inet6_hashtables.h>
 #include <net/tcp_states.h>
 #include <net/protocol.h>
 #include <net/xfrm.h>
@@ -56,24 +57,36 @@ static inline struct l2tp_ip6_sock *l2tp_ip6_sk(const struct sock *sk)
 	return (struct l2tp_ip6_sock *)sk;
 }
 
-static struct sock *__l2tp_ip6_bind_lookup(struct net *net,
-					   struct in6_addr *laddr,
+static struct sock *__l2tp_ip6_bind_lookup(const struct net *net,
+					   const struct in6_addr *laddr,
+					   const struct in6_addr *raddr,
 					   int dif, u32 tunnel_id)
 {
 	struct sock *sk;
 
 	sk_for_each_bound(sk, &l2tp_ip6_bind_table) {
-		const struct in6_addr *addr = inet6_rcv_saddr(sk);
-		struct l2tp_ip6_sock *l2tp = l2tp_ip6_sk(sk);
+		const struct in6_addr *sk_laddr = inet6_rcv_saddr(sk);
+		const struct in6_addr *sk_raddr = &sk->sk_v6_daddr;
+		const struct l2tp_ip6_sock *l2tp = l2tp_ip6_sk(sk);
 
-		if (l2tp == NULL)
+		if (!net_eq(sock_net(sk), net))
 			continue;
 
-		if ((l2tp->conn_id == tunnel_id) &&
-		    net_eq(sock_net(sk), net) &&
-		    !(addr && ipv6_addr_equal(addr, laddr)) &&
-		    !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
-			goto found;
+		if (sk->sk_bound_dev_if && dif && sk->sk_bound_dev_if != dif)
+			continue;
+
+		if (sk_laddr && !ipv6_addr_any(sk_laddr) &&
+		    !ipv6_addr_any(laddr) && !ipv6_addr_equal(sk_laddr, laddr))
+			continue;
+
+		if (!ipv6_addr_any(sk_raddr) && raddr &&
+		    !ipv6_addr_any(raddr) && !ipv6_addr_equal(sk_raddr, raddr))
+			continue;
+
+		if (l2tp->conn_id != tunnel_id)
+			continue;
+
+		goto found;
 	}
 
 	sk = NULL;
@@ -81,17 +94,6 @@ found:
 	return sk;
 }
 
-static inline struct sock *l2tp_ip6_bind_lookup(struct net *net,
-						struct in6_addr *laddr,
-						int dif, u32 tunnel_id)
-{
-	struct sock *sk = __l2tp_ip6_bind_lookup(net, laddr, dif, tunnel_id);
-	if (sk)
-		sock_hold(sk);
-
-	return sk;
-}
-
 /* When processing receive frames, there are two cases to
  * consider. Data frames consist of a non-zero session-id and an
  * optional cookie. Control frames consist of a regular L2TP header
@@ -127,6 +129,7 @@ static inline struct sock *l2tp_ip6_bind_lookup(struct net *net,
  */
 static int l2tp_ip6_recv(struct sk_buff *skb)
 {
+	struct net *net = dev_net(skb->dev);
 	struct sock *sk;
 	u32 session_id;
 	u32 tunnel_id;
@@ -135,12 +138,11 @@ static int l2tp_ip6_recv(struct sk_buff *skb)
 	struct l2tp_tunnel *tunnel = NULL;
 	int length;
 
-	/* Point to L2TP header */
-	optr = ptr = skb->data;
-
 	if (!pskb_may_pull(skb, 4))
 		goto discard;
 
+	/* Point to L2TP header */
+	optr = ptr = skb->data;
 	session_id = ntohl(*((__be32 *) ptr));
 	ptr += 4;
 
@@ -154,26 +156,31 @@ static int l2tp_ip6_recv(struct sk_buff *skb)
 	}
 
 	/* Ok, this is a data packet. Lookup the session. */
-	session = l2tp_session_find(&init_net, NULL, session_id);
-	if (session == NULL)
+	session = l2tp_session_get(net, NULL, session_id, true);
+	if (!session)
 		goto discard;
 
 	tunnel = session->tunnel;
-	if (tunnel == NULL)
-		goto discard;
+	if (!tunnel)
+		goto discard_sess;
 
 	/* Trace packet contents, if enabled */
 	if (tunnel->debug & L2TP_MSG_DATA) {
 		length = min(32u, skb->len);
 		if (!pskb_may_pull(skb, length))
-			goto discard;
+			goto discard_sess;
 
+		/* Point to L2TP header */
+		optr = ptr = skb->data;
+		ptr += 4;
 		pr_debug("%s: ip recv\n", tunnel->name);
 		print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, ptr, length);
 	}
 
 	l2tp_recv_common(session, skb, ptr, optr, 0, skb->len,
 			 tunnel->recv_payload_hook);
+	l2tp_session_dec_refcount(session);
+
 	return 0;
 
 pass_up:
@@ -185,23 +192,25 @@ pass_up:
 		goto discard;
 
 	tunnel_id = ntohl(*(__be32 *) &skb->data[4]);
-	tunnel = l2tp_tunnel_find(&init_net, tunnel_id);
-	if (tunnel != NULL)
+	tunnel = l2tp_tunnel_find(net, tunnel_id);
+	if (tunnel) {
 		sk = tunnel->sock;
-	else {
+		sock_hold(sk);
+	} else {
 		struct ipv6hdr *iph = ipv6_hdr(skb);
 
 		read_lock_bh(&l2tp_ip6_lock);
-		sk = __l2tp_ip6_bind_lookup(&init_net, &iph->daddr,
-					    0, tunnel_id);
+		sk = __l2tp_ip6_bind_lookup(net, &iph->daddr, &iph->saddr,
+					    inet6_iif(skb), tunnel_id);
+		if (!sk) {
+			read_unlock_bh(&l2tp_ip6_lock);
+			goto discard;
+		}
+
+		sock_hold(sk);
 		read_unlock_bh(&l2tp_ip6_lock);
 	}
 
-	if (sk == NULL)
-		goto discard;
-
-	sock_hold(sk);
-
 	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 		goto discard_put;
 
@@ -209,6 +218,12 @@ pass_up:
 
 	return sk_receive_skb(sk, skb, 1);
 
+discard_sess:
+	if (session->deref)
+		session->deref(session);
+	l2tp_session_dec_refcount(session);
+	goto discard;
+
 discard_put:
 	sock_put(sk);
 
@@ -260,12 +275,12 @@ static int l2tp_ip6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	struct inet_sock *inet = inet_sk(sk);
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	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;
 
-	if (!sock_flag(sk, SOCK_ZAPPED))
-		return -EINVAL;
 	if (addr->l2tp_family != AF_INET6)
 		return -EINVAL;
 	if (addr_len < sizeof(*addr))
@@ -281,41 +296,34 @@ 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(&init_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;
+	if (!sock_flag(sk, SOCK_ZAPPED))
+		goto out_unlock;
+
 	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;
 		}
@@ -330,13 +338,22 @@ 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, NULL, 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);
@@ -349,10 +366,7 @@ out_unlock_rcu:
 	rcu_read_unlock();
 out_unlock:
 	release_sock(sk);
-	return err;
 
-out_in_use:
-	read_unlock_bh(&l2tp_ip6_lock);
 	return err;
 }
 
@@ -365,9 +379,6 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
 	int	addr_type;
 	int rc;
 
-	if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
-		return -EINVAL;
-
 	if (addr_len < sizeof(*lsa))
 		return -EINVAL;
 
@@ -384,10 +395,18 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
 			return -EINVAL;
 	}
 
-	rc = ip6_datagram_connect(sk, uaddr, addr_len);
-
 	lock_sock(sk);
 
+	 /* Must bind first - autobinding does not work */
+	if (sock_flag(sk, SOCK_ZAPPED)) {
+		rc = -EINVAL;
+		goto out_sk;
+	}
+
+	rc = __ip6_datagram_connect(sk, uaddr, addr_len);
+	if (rc < 0)
+		goto out_sk;
+
 	l2tp_ip6_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
 
 	write_lock_bh(&l2tp_ip6_lock);
@@ -395,6 +414,7 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
 	sk_add_bind_node(sk, &l2tp_ip6_bind_table);
 	write_unlock_bh(&l2tp_ip6_lock);
 
+out_sk:
 	release_sock(sk);
 
 	return rc;
@@ -405,7 +425,7 @@ static int l2tp_ip6_disconnect(struct sock *sk, int flags)
 	if (sock_flag(sk, SOCK_ZAPPED))
 		return 0;
 
-	return udp_disconnect(sk, flags);
+	return __udp_disconnect(sk, flags);
 }
 
 static int l2tp_ip6_getname(struct socket *sock, struct sockaddr *uaddr,
@@ -453,7 +473,7 @@ static int l2tp_ip6_backlog_recv(struct sock *sk, struct sk_buff *skb)
 	return 0;
 
 drop:
-	IP_INC_STATS(&init_net, IPSTATS_MIB_INDISCARDS);
+	IP_INC_STATS(sock_net(sk), IPSTATS_MIB_INDISCARDS);
 	kfree_skb(skb);
 	return -1;
 }
@@ -491,10 +511,9 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	struct ip6_flowlabel *flowlabel = NULL;
 	struct dst_entry *dst = NULL;
 	struct flowi6 fl6;
+	struct sockcm_cookie sockc_unused = {0};
+	struct ipcm6_cookie ipc6;
 	int addr_len = msg->msg_namelen;
-	int hlimit = -1;
-	int tclass = -1;
-	int dontfrag = -1;
 	int transhdrlen = 4; /* zero session-id */
 	int ulen = len + transhdrlen;
 	int err;
@@ -515,6 +534,11 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	memset(&fl6, 0, sizeof(fl6));
 
 	fl6.flowi6_mark = sk->sk_mark;
+	fl6.flowi6_uid = sk->sk_uid;
+
+	ipc6.hlimit = -1;
+	ipc6.tclass = -1;
+	ipc6.dontfrag = -1;
 
 	if (lsa) {
 		if (addr_len < SIN6_LEN_RFC2133)
@@ -560,9 +584,10 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 		opt = &opt_space;
 		memset(opt, 0, sizeof(struct ipv6_txoptions));
 		opt->tot_len = sizeof(struct ipv6_txoptions);
+		ipc6.opt = opt;
 
-		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
-					    &hlimit, &tclass, &dontfrag);
+		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6,
+					    &sockc_unused);
 		if (err < 0) {
 			fl6_sock_release(flowlabel);
 			return err;
@@ -583,6 +608,7 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	if (flowlabel)
 		opt = fl6_merge_options(&opt_space, flowlabel, opt);
 	opt = ipv6_fixup_options(&opt_space, opt);
+	ipc6.opt = opt;
 
 	fl6.flowi6_proto = sk->sk_protocol;
 	if (!ipv6_addr_any(daddr))
@@ -601,20 +627,22 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
 	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 
+	if (ipc6.tclass < 0)
+		ipc6.tclass = np->tclass;
+
+	fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
+
 	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		goto out;
 	}
 
-	if (hlimit < 0)
-		hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
-
-	if (tclass < 0)
-		tclass = np->tclass;
+	if (ipc6.hlimit < 0)
+		ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 
-	if (dontfrag < 0)
-		dontfrag = np->dontfrag;
+	if (ipc6.dontfrag < 0)
+		ipc6.dontfrag = np->dontfrag;
 
 	if (msg->msg_flags & MSG_CONFIRM)
 		goto do_confirm;
@@ -622,9 +650,9 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 back_from_confirm:
 	lock_sock(sk);
 	err = ip6_append_data(sk, ip_generic_getfrag, msg,
-			      ulen, transhdrlen, hlimit, tclass, opt,
+			      ulen, transhdrlen, &ipc6,
 			      &fl6, (struct rt6_info *)dst,
-			      msg->msg_flags, dontfrag);
+			      msg->msg_flags, &sockc_unused);
 	if (err)
 		ip6_flush_pending_frames(sk);
 	else if (!(msg->msg_flags & MSG_MORE))
@@ -639,7 +667,8 @@ out:
 	return err < 0 ? err : len;
 
 do_confirm:
-	dst_confirm(dst);
+	if (msg->msg_flags & MSG_PROBE)
+		dst_confirm_neigh(dst, &fl6.daddr);
 	if (!(msg->msg_flags & MSG_PROBE) || len)
 		goto back_from_confirm;
 	err = 0;
@@ -711,14 +740,14 @@ static struct proto l2tp_ip6_prot = {
 	.bind		   = l2tp_ip6_bind,
 	.connect	   = l2tp_ip6_connect,
 	.disconnect	   = l2tp_ip6_disconnect,
-	.ioctl		   = udp_ioctl,
+	.ioctl		   = l2tp_ioctl,
 	.destroy	   = l2tp_ip6_destroy_sock,
 	.setsockopt	   = ipv6_setsockopt,
 	.getsockopt	   = ipv6_getsockopt,
 	.sendmsg	   = l2tp_ip6_sendmsg,
 	.recvmsg	   = l2tp_ip6_recvmsg,
 	.backlog_rcv	   = l2tp_ip6_backlog_recv,
-	.hash		   = inet_hash,
+	.hash		   = inet6_hash,
 	.unhash		   = inet_unhash,
 	.obj_size	   = sizeof(struct l2tp_ip6_sock),
 #ifdef CONFIG_COMPAT