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

[James Chapman <jchapman@katalix.com>]

---
 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