From 3ba359c0cd6eb5ea772125a7aededb4a2d516684 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 19 Jul 2024 09:41:18 -0700 Subject: [PATCH] net: bonding: correctly annotate RCU in bond_should_notify_peers() RCU use in bond_should_notify_peers() looks wrong, since it does rcu_dereference(), leaves the critical section, and uses the pointer after that. Luckily, it's called either inside a nested RCU critical section or with the RTNL held. Annotate it with rcu_dereference_rtnl() instead, and remove the inner RCU critical section. Fixes: 4cb4f97b7e36 ("bonding: rebuild the lock use for bond_mii_monitor()") Reviewed-by: Jiri Pirko Signed-off-by: Johannes Berg Acked-by: Jay Vosburgh Link: https://patch.msgid.link/20240719094119.35c62455087d.I68eb9c0f02545b364b79a59f2110f2cf5682a8e2@changeid Signed-off-by: Paolo Abeni --- drivers/net/bonding/bond_main.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index af9ddd3902cc9..1cd92c12e7824 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1121,13 +1121,10 @@ static struct slave *bond_find_best_slave(struct bonding *bond) return bestslave; } +/* must be called in RCU critical section or with RTNL held */ static bool bond_should_notify_peers(struct bonding *bond) { - struct slave *slave; - - rcu_read_lock(); - slave = rcu_dereference(bond->curr_active_slave); - rcu_read_unlock(); + struct slave *slave = rcu_dereference_rtnl(bond->curr_active_slave); if (!slave || !bond->send_peer_notif || bond->send_peer_notif %