net: bonding: add the READ_ONCE/WRITE_ONCE for outside lock accessing

Although operations on the variable send_peer_notif are already within
a lock-protected critical section, there are cases where it is accessed
outside the lock. Therefore, READ_ONCE() and WRITE_ONCE() should be
added to it.

Cc: Jay Vosburgh <jv@jvosburgh.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Cc: Hangbin Liu <liuhangbin@gmail.com>
Cc: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Tonghao Zhang <tonghao@bamaicloud.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://patch.msgid.link/c1dcc53442f4d0f67beb9e0a3e7a7a6a2c94c47f.1768709239.git.tonghao@bamaicloud.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 98f391ac761f8b2fad32338ce07e0d4f7737a89a..b7923d052a8df42f37394be14d84f5c4ab9d58c5 100644 (file)
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1204,8 +1204,9 @@ void bond_peer_notify_work_rearm(struct bonding *bond, unsigned long delay)
 /* Peer notify update handler. Holds only RTNL */
 static void bond_peer_notify_reset(struct bonding *bond)
 {
-       bond->send_peer_notif = bond->params.num_peer_notif *
-               max(1, bond->params.peer_notif_delay);
+       WRITE_ONCE(bond->send_peer_notif,
+                  bond->params.num_peer_notif *
+                  max(1, bond->params.peer_notif_delay));
 }
 
 static void bond_peer_notify_handler(struct work_struct *work)
@@ -2832,7 +2833,7 @@ static void bond_mii_monitor(struct work_struct *work)
 
        rcu_read_unlock();
 
-       if (commit || bond->send_peer_notif) {
+       if (commit || READ_ONCE(bond->send_peer_notif)) {
                /* Race avoidance with bond_close cancel of workqueue */
                if (!rtnl_trylock()) {
                        delay = 1;
@@ -3787,7 +3788,7 @@ static void bond_activebackup_arp_mon(struct bonding *bond)
        should_notify_rtnl = bond_ab_arp_probe(bond);
        rcu_read_unlock();
 
-       if (bond->send_peer_notif || should_notify_rtnl) {
+       if (READ_ONCE(bond->send_peer_notif) || should_notify_rtnl) {
                if (!rtnl_trylock()) {
                        delta_in_ticks = 1;
                        goto re_arm;