From b5a3caa4193ad0f66ef2fb597c6d610817dea7d2 Mon Sep 17 00:00:00 2001 From: James Chapman Date: Mon, 29 Jul 2024 16:38:08 +0100 Subject: [PATCH] l2tp: free sessions using rcu BugLink: https://bugs.launchpad.net/bugs/2097301 [ Upstream commit d17e89999574aca143dd4ede43e4382d32d98724 ] l2tp sessions may be accessed under an rcu read lock. Have them freed via rcu and remove the now unneeded synchronize_rcu when a session is removed. Signed-off-by: James Chapman Signed-off-by: Tom Parkin Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Manuel Diewald Signed-off-by: Koichiro Den --- net/l2tp/l2tp_core.c | 4 +--- net/l2tp/l2tp_core.h | 1 + 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index 87285f4fb7bc..8d56f59e776e 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -165,7 +165,7 @@ static void l2tp_session_free(struct l2tp_session *session) trace_free_session(session); if (session->tunnel) l2tp_tunnel_dec_refcount(session->tunnel); - kfree(session); + kfree_rcu(session, rcu); } struct l2tp_tunnel *l2tp_sk_to_tunnel(struct sock *sk) @@ -1214,8 +1214,6 @@ static void l2tp_session_unhash(struct l2tp_session *session) hlist_del_init_rcu(&session->global_hlist); spin_unlock_bh(&pn->l2tp_session_hlist_lock); } - - synchronize_rcu(); } } diff --git a/net/l2tp/l2tp_core.h b/net/l2tp/l2tp_core.h index 91ebf0a3f499..9d407efd9b2e 100644 --- a/net/l2tp/l2tp_core.h +++ b/net/l2tp/l2tp_core.h @@ -70,6 +70,7 @@ struct l2tp_session_cfg { struct l2tp_session { int magic; /* should be L2TP_SESSION_MAGIC */ long dead; + struct rcu_head rcu; struct l2tp_tunnel *tunnel; /* back pointer to tunnel context */ u32 session_id;