From f74da2c2546c402cd2fc4165ef54b48cce6e39cc Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Fri, 4 Jun 2021 17:17:33 +0200 Subject: [PATCH] wireguard: use synchronize_net rather than synchronize_rcu commit 24b70eeeb4f46c09487f8155239ebfb1f875774a upstream. Many of the synchronization points are sometimes called under the rtnl lock, which means we should use synchronize_net rather than synchronize_rcu. Under the hood, this expands to using the expedited flavor of function in the event that rtnl is held, in order to not stall other concurrent changes. This fixes some very, very long delays when removing multiple peers at once, which would cause some operations to take several minutes. Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireguard/peer.c | 6 +++--- drivers/net/wireguard/socket.c | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireguard/peer.c b/drivers/net/wireguard/peer.c index 6936a82..1acd00a 100644 --- a/drivers/net/wireguard/peer.c +++ b/drivers/net/wireguard/peer.c @@ -89,7 +89,7 @@ static void peer_make_dead(struct wg_peer *peer) /* Mark as dead, so that we don't allow jumping contexts after. */ WRITE_ONCE(peer->is_dead, true); - /* The caller must now synchronize_rcu() for this to take effect. */ + /* The caller must now synchronize_net() for this to take effect. */ } static void peer_remove_after_dead(struct wg_peer *peer) @@ -161,7 +161,7 @@ void wg_peer_remove(struct wg_peer *peer) lockdep_assert_held(&peer->device->device_update_lock); peer_make_dead(peer); - synchronize_rcu(); + synchronize_net(); peer_remove_after_dead(peer); } @@ -179,7 +179,7 @@ void wg_peer_remove_all(struct wg_device *wg) peer_make_dead(peer); list_add_tail(&peer->peer_list, &dead_peers); } - synchronize_rcu(); + synchronize_net(); list_for_each_entry_safe(peer, temp, &dead_peers, peer_list) peer_remove_after_dead(peer); } diff --git a/drivers/net/wireguard/socket.c b/drivers/net/wireguard/socket.c index c33e2c8..c8cd385 100644 --- a/drivers/net/wireguard/socket.c +++ b/drivers/net/wireguard/socket.c @@ -430,7 +430,7 @@ void wg_socket_reinit(struct wg_device *wg, struct sock *new4, if (new4) wg->incoming_port = ntohs(inet_sk(new4)->inet_sport); mutex_unlock(&wg->socket_update_lock); - synchronize_rcu(); + synchronize_net(); sock_free(old4); sock_free(old6); } -- 2.7.4