From de7e69e6d7dec456b692e374c81399f9174a33cb Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Fri, 4 Jun 2021 17:17:33 +0200 Subject: [PATCH] UPSTREAM: wireguard: use synchronize_net rather than synchronize_rcu 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 (cherry picked from commit 24b70eeeb4f46c09487f8155239ebfb1f875774a) Signed-off-by: Greg Kroah-Hartman Change-Id: I84184bb3e38c9dd5eda7d09b913d37b7a9e63396 --- 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 1d634bd3038f..01b311138365 100644 --- a/drivers/net/wireguard/peer.c +++ b/drivers/net/wireguard/peer.c @@ -97,7 +97,7 @@ 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) @@ -169,7 +169,7 @@ 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); } @@ -187,7 +187,7 @@ 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 c33e2c81635f..c8cd385d233b 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); }