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Diffstat (limited to 'net/l2tp/l2tp_core.c')
-rw-r--r--net/l2tp/l2tp_core.c117
1 files changed, 34 insertions, 83 deletions
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
index 9cd2a99d0752..0fa53ead24aa 100644
--- a/net/l2tp/l2tp_core.c
+++ b/net/l2tp/l2tp_core.c
@@ -136,51 +136,6 @@ l2tp_session_id_hash_2(struct l2tp_net *pn, u32 session_id)
}
-/* Lookup the tunnel socket, possibly involving the fs code if the socket is
- * owned by userspace. A struct sock returned from this function must be
- * released using l2tp_tunnel_sock_put once you're done with it.
- */
-static struct sock *l2tp_tunnel_sock_lookup(struct l2tp_tunnel *tunnel)
-{
- int err = 0;
- struct socket *sock = NULL;
- struct sock *sk = NULL;
-
- if (!tunnel)
- goto out;
-
- if (tunnel->fd >= 0) {
- /* Socket is owned by userspace, who might be in the process
- * of closing it. Look the socket up using the fd to ensure
- * consistency.
- */
- sock = sockfd_lookup(tunnel->fd, &err);
- if (sock)
- sk = sock->sk;
- } else {
- /* Socket is owned by kernelspace */
- sk = tunnel->sock;
- sock_hold(sk);
- }
-
-out:
- return sk;
-}
-
-/* Drop a reference to a tunnel socket obtained via. l2tp_tunnel_sock_put */
-static void l2tp_tunnel_sock_put(struct sock *sk)
-{
- struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk);
- if (tunnel) {
- if (tunnel->fd >= 0) {
- /* Socket is owned by userspace */
- sockfd_put(sk->sk_socket);
- }
- sock_put(sk);
- }
- sock_put(sk);
-}
-
/* Session hash list.
* The session_id SHOULD be random according to RFC2661, but several
* L2TP implementations (Cisco and Microsoft) use incrementing
@@ -193,6 +148,13 @@ l2tp_session_id_hash(struct l2tp_tunnel *tunnel, u32 session_id)
return &tunnel->session_hlist[hash_32(session_id, L2TP_HASH_BITS)];
}
+void l2tp_tunnel_free(struct l2tp_tunnel *tunnel)
+{
+ sock_put(tunnel->sock);
+ /* the tunnel is freed in the socket destructor */
+}
+EXPORT_SYMBOL(l2tp_tunnel_free);
+
/* Lookup a tunnel. A new reference is held on the returned tunnel. */
struct l2tp_tunnel *l2tp_tunnel_get(const struct net *net, u32 tunnel_id)
{
@@ -345,13 +307,11 @@ int l2tp_session_register(struct l2tp_session *session,
}
l2tp_tunnel_inc_refcount(tunnel);
- sock_hold(tunnel->sock);
hlist_add_head_rcu(&session->global_hlist, g_head);
spin_unlock_bh(&pn->l2tp_session_hlist_lock);
} else {
l2tp_tunnel_inc_refcount(tunnel);
- sock_hold(tunnel->sock);
}
hlist_add_head(&session->hlist, head);
@@ -969,7 +929,7 @@ int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
{
struct l2tp_tunnel *tunnel;
- tunnel = l2tp_sock_to_tunnel(sk);
+ tunnel = l2tp_tunnel(sk);
if (tunnel == NULL)
goto pass_up;
@@ -977,13 +937,10 @@ int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
tunnel->name, skb->len);
if (l2tp_udp_recv_core(tunnel, skb, tunnel->recv_payload_hook))
- goto pass_up_put;
+ goto pass_up;
- sock_put(sk);
return 0;
-pass_up_put:
- sock_put(sk);
pass_up:
return 1;
}
@@ -1214,7 +1171,6 @@ static void l2tp_tunnel_destruct(struct sock *sk)
l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing...\n", tunnel->name);
-
/* Disable udp encapsulation */
switch (tunnel->encap) {
case L2TP_ENCAPTYPE_UDP:
@@ -1237,12 +1193,11 @@ static void l2tp_tunnel_destruct(struct sock *sk)
list_del_rcu(&tunnel->list);
spin_unlock_bh(&pn->l2tp_tunnel_list_lock);
- tunnel->sock = NULL;
- l2tp_tunnel_dec_refcount(tunnel);
-
/* Call the original destructor */
if (sk->sk_destruct)
(*sk->sk_destruct)(sk);
+
+ kfree_rcu(tunnel, rcu);
end:
return;
}
@@ -1303,30 +1258,22 @@ EXPORT_SYMBOL_GPL(l2tp_tunnel_closeall);
/* Tunnel socket destroy hook for UDP encapsulation */
static void l2tp_udp_encap_destroy(struct sock *sk)
{
- struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk);
- if (tunnel) {
- l2tp_tunnel_closeall(tunnel);
- sock_put(sk);
- }
+ struct l2tp_tunnel *tunnel = l2tp_tunnel(sk);
+
+ if (tunnel)
+ l2tp_tunnel_delete(tunnel);
}
/* Workqueue tunnel deletion function */
static void l2tp_tunnel_del_work(struct work_struct *work)
{
- struct l2tp_tunnel *tunnel = NULL;
- struct socket *sock = NULL;
- struct sock *sk = NULL;
-
- tunnel = container_of(work, struct l2tp_tunnel, del_work);
+ struct l2tp_tunnel *tunnel = container_of(work, struct l2tp_tunnel,
+ del_work);
+ struct sock *sk = tunnel->sock;
+ struct socket *sock = sk->sk_socket;
l2tp_tunnel_closeall(tunnel);
- sk = l2tp_tunnel_sock_lookup(tunnel);
- if (!sk)
- goto out;
-
- sock = sk->sk_socket;
-
/* If the tunnel socket was created within the kernel, use
* the sk API to release it here.
*/
@@ -1337,8 +1284,10 @@ static void l2tp_tunnel_del_work(struct work_struct *work)
}
}
- l2tp_tunnel_sock_put(sk);
-out:
+ /* drop initial ref */
+ l2tp_tunnel_dec_refcount(tunnel);
+
+ /* drop workqueue ref */
l2tp_tunnel_dec_refcount(tunnel);
}
@@ -1591,13 +1540,22 @@ int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32
sk->sk_user_data = tunnel;
}
+ /* Bump the reference count. The tunnel context is deleted
+ * only when this drops to zero. A reference is also held on
+ * the tunnel socket to ensure that it is not released while
+ * the tunnel is extant. Must be done before sk_destruct is
+ * set.
+ */
+ refcount_set(&tunnel->ref_count, 1);
+ sock_hold(sk);
+ tunnel->sock = sk;
+ tunnel->fd = fd;
+
/* Hook on the tunnel socket destructor so that we can cleanup
* if the tunnel socket goes away.
*/
tunnel->old_sk_destruct = sk->sk_destruct;
sk->sk_destruct = &l2tp_tunnel_destruct;
- tunnel->sock = sk;
- tunnel->fd = fd;
lockdep_set_class_and_name(&sk->sk_lock.slock, &l2tp_socket_class, "l2tp_sock");
sk->sk_allocation = GFP_ATOMIC;
@@ -1607,11 +1565,6 @@ int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32
/* Add tunnel to our list */
INIT_LIST_HEAD(&tunnel->list);
-
- /* Bump the reference count. The tunnel context is deleted
- * only when this drops to zero. Must be done before list insertion
- */
- refcount_set(&tunnel->ref_count, 1);
spin_lock_bh(&pn->l2tp_tunnel_list_lock);
list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list);
spin_unlock_bh(&pn->l2tp_tunnel_list_lock);
@@ -1652,8 +1605,6 @@ void l2tp_session_free(struct l2tp_session *session)
if (tunnel) {
BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC);
- sock_put(tunnel->sock);
- session->tunnel = NULL;
l2tp_tunnel_dec_refcount(tunnel);
}