[SRU][N][PATCH 1/2] net: bonding: update the slave array for broadcast mode

[Edoardo Canepa]

From: Tonghao Zhang <tonghao at bamaicloud.com>

BugLink: https://bugs.launchpad.net/bugs/2153556

This patch fixes ce7a381697cb ("net: bonding: add broadcast_neighbor option for 802.3ad").
Before this commit, on the broadcast mode, all devices were traversed using the
bond_for_each_slave_rcu. This patch supports traversing devices by using all_slaves.
Therefore, we need to update the slave array when enslave or release slave.

Fixes: ce7a381697cb ("net: bonding: add broadcast_neighbor option for 802.3ad")
Cc: Simon Horman <horms at kernel.org>
Cc: Jonathan Corbet <corbet at lwn.net>
Cc: Andrew Lunn <andrew+netdev at lunn.ch>
Cc: <stable at vger.kernel.org>
Reported-by: Jiri Slaby <jirislaby at kernel.org>
Tested-by: Jiri Slaby <jirislaby at kernel.org>
Link: https://lore.kernel.org/all/a97e6e1e-81bc-4a79-8352-9e4794b0d2ca@kernel.org/
Signed-off-by: Tonghao Zhang <tonghao at bamaicloud.com>
Reviewed-by: Hangbin Liu <liuhangbin at gmail.com>
Reviewed-by: Nikolay Aleksandrov <razor at blackwall.org>
Acked-by: Jay Vosburgh <jv at jvosburgh.net>
Link: https://patch.msgid.link/20251016125136.16568-1-tonghao@bamaicloud.com
Signed-off-by: Jakub Kicinski <kuba at kernel.org>
(cherry picked from commit e0caeb24f538c3c9c94f471882ceeb43d9dc2739)
Signed-off-by: Edoardo Canepa <edoardo.canepa at canonical.com>
---
 drivers/net/bonding/bond_main.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 21e0b7b13052..93ef49ad6273 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2305,7 +2305,9 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 		unblock_netpoll_tx();
 	}
 
-	if (bond_mode_can_use_xmit_hash(bond))
+	/* broadcast mode uses the all_slaves to loop through slaves. */
+	if (bond_mode_can_use_xmit_hash(bond) ||
+	    BOND_MODE(bond) == BOND_MODE_BROADCAST)
 		bond_update_slave_arr(bond, NULL);
 
 	if (!slave_dev->netdev_ops->ndo_bpf ||
@@ -2481,7 +2483,8 @@ static int __bond_release_one(struct net_device *bond_dev,
 
 	bond_upper_dev_unlink(bond, slave);
 
-	if (bond_mode_can_use_xmit_hash(bond))
+	if (bond_mode_can_use_xmit_hash(bond) ||
+	    BOND_MODE(bond) == BOND_MODE_BROADCAST)
 		bond_update_slave_arr(bond, slave);
 
 	slave_info(bond_dev, slave_dev, "Releasing %s interface\n",
-- 
2.51.0