[PATCH net-next v2 08/16] l2tp: hide session from pppol2tp_sock_to_session if it is closing

[James Chapman]

---
 net/l2tp/l2tp_ppp.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index ff95a4d4eac5..947066b3d6d8 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -172,8 +172,16 @@ static inline struct l2tp_session 
*pppol2tp_sock_to_session(struct sock *sk)
                rcu_read_unlock_bh();
                return NULL;
        }
+
+       spin_lock_bh(&session->lock);
+       if (session->closing) {
+               spin_unlock_bh(&session->lock);
+               rcu_read_unlock_bh();
+               return NULL;
+       }
        l2tp_session_inc_refcount(session);
-       rcu_read_unlock();
+       spin_unlock_bh(&session->lock);
+       rcu_read_unlock_bh();
 
        BUG_ON(session->magic != L2TP_SESSION_MAGIC);
 
-- 
1.9.1