l2tp: avoid to use synchronize_rcu in tunnel free function

[ Upstream commit 99469c32f79a32d8481f87be0d3c66dad286f4ec ]

Avoid to use synchronize_rcu in l2tp_tunnel_free because context may be
atomic.

Signed-off-by: Dmitry Kozlov <xeb@mail.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
index 89ff8c6..7501b22 100644 (file)
--- a/net/l2tp/l2tp_core.c
+++ b/net/l2tp/l2tp_core.c
@@ -1253,11 +1253,10 @@ static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel)
        /* Remove from tunnel list */
        spin_lock_bh(&pn->l2tp_tunnel_list_lock);
        list_del_rcu(&tunnel->list);
+       kfree_rcu(tunnel, rcu);
        spin_unlock_bh(&pn->l2tp_tunnel_list_lock);
-       synchronize_rcu();
 
        atomic_dec(&l2tp_tunnel_count);
-       kfree(tunnel);
 }
 
 /* Create a socket for the tunnel, if one isn't set up by

diff --git a/net/l2tp/l2tp_core.h b/net/l2tp/l2tp_core.h
index a16a48e..4393794 100644 (file)
--- a/net/l2tp/l2tp_core.h
+++ b/net/l2tp/l2tp_core.h
@@ -157,6 +157,7 @@ struct l2tp_tunnel_cfg {
 
 struct l2tp_tunnel {
        int                     magic;          /* Should be L2TP_TUNNEL_MAGIC */
+       struct rcu_head rcu;
        rwlock_t                hlist_lock;     /* protect session_hlist */
        struct hlist_head       session_hlist[L2TP_HASH_SIZE];
                                                /* hashed list of sessions,