[PATCH net] bonding: Avoid possible de-sync with arp_validate

[Marcelo Ricardo Leitner <mleitner@redhat.com>]

Hi Dave,

Please queue this one for -stable trees too.

Thanks.

---8<---

As bond_store_arp_validation and bond_store_arp_interval doesn't
deal with each other, we can't chain both at bond_open, otherwise
we are open to this de-sync state, steps in sequence:
- bond is down
- arp_interval = 0
- arp_validate = 1 or 2
- bond is up
- arp_interval = 1

This would lead to bond issuing ARP requests but never listening
to the replies, because the tap wasn't attached. After reaching
this state, while bond is up, setting arp_validate won't help
as it only acts if needed.
---
 drivers/net/bonding/bond_main.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 39e5b1c..805d098 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -3180,11 +3180,10 @@ static int bond_open(struct net_device *bond_dev)
 	if (bond->params.miimon)  /* link check interval, in milliseconds. */
 		queue_delayed_work(bond->wq, &bond->mii_work, 0);
 
-	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
+	if (bond->params.arp_interval)    /* arp interval, in milliseconds. */
 		queue_delayed_work(bond->wq, &bond->arp_work, 0);
-		if (bond->params.arp_validate)
-			bond->recv_probe = bond_arp_rcv;
-	}
+	if (bond->params.arp_validate)
+		bond->recv_probe = bond_arp_rcv;
 
 	if (bond->params.mode == BOND_MODE_8023AD) {
 		queue_delayed_work(bond->wq, &bond->ad_work, 0);
-- 
1.8.3.1