Commit 89b768ec authored by James Chapman's avatar James Chapman Committed by David S. Miller
Browse files

l2tp: use rcu list add/del when updating lists 



l2tp_v3_session_htable and tunnel->session_list are read by lockless
getters using RCU. Use rcu list variants when adding or removing list
items.

Signed-off-by: default avatarJames Chapman <jchapman@katalix.com>
Signed-off-by: default avatarTom Parkin <tparkin@katalix.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 24256415

net/l2tp/l2tp_core.c

+6 −6
Original line number Diff line number Diff line
@@ -419,11 +419,11 @@ static int l2tp_session_collision_add(struct l2tp_net *pn, 


	/* If existing session isn't already in the session hlist, add it. */

	if (!hash_hashed(&session2->hlist))

		hash_add(pn->l2tp_v3_session_htable, &session2->hlist,

		hash_add_rcu(pn->l2tp_v3_session_htable, &session2->hlist,

			     session2->hlist_key);



	/* Add new session to the hlist and collision list */

	hash_add(pn->l2tp_v3_session_htable, &session1->hlist,

	hash_add_rcu(pn->l2tp_v3_session_htable, &session1->hlist,

		     session1->hlist_key);

	refcount_inc(&clist->ref_count);

	l2tp_session_coll_list_add(clist, session1);
@@ -440,7 +440,7 @@ static void l2tp_session_collision_del(struct l2tp_net *pn, 


	lockdep_assert_held(&pn->l2tp_session_idr_lock);



	hash_del(&session->hlist);

	hash_del_rcu(&session->hlist);



	if (clist) {

		/* Remove session from its collision list. If there
@@ -515,7 +515,7 @@ int l2tp_session_register(struct l2tp_session *session, 


	l2tp_tunnel_inc_refcount(tunnel);

	WRITE_ONCE(session->tunnel, tunnel);

	list_add(&session->list, &tunnel->session_list);

	list_add_rcu(&session->list, &tunnel->session_list);



	if (tunnel->version == L2TP_HDR_VER_3) {

		if (!other_session)