Re: [PATCH net 4/4] bonding: fix xfrm state handling when clearing active slave

[Hangbin Liu <liuhangbin@gmail.com>]

On Mon, Aug 19, 2024 at 10:38:01AM +0300, Nikolay Aleksandrov wrote:
> >> diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
> >> index bc80fb6397dc..95d59a18c022 100644
> >> --- a/drivers/net/bonding/bond_options.c
> >> +++ b/drivers/net/bonding/bond_options.c
> >> @@ -936,7 +936,7 @@ static int bond_option_active_slave_set(struct bonding *bond,
> >>  	/* check to see if we are clearing active */
> >>  	if (!slave_dev) {
> >>  		netdev_dbg(bond->dev, "Clearing current active slave\n");
> >> -		RCU_INIT_POINTER(bond->curr_active_slave, NULL);
> >> +		bond_change_active_slave(bond, NULL);
> > 
> > The good part of this is we can do bond_ipsec_del_sa_all and
> > bond_ipsec_add_sa_all. I'm not sure if we should do promisc/mcast adjustment
> > when set active_slave to null.
> > 
> > Jay should know better.
> > 
> > Thanks
> > Hangbin
> 
> Jay please correct me, but I'm pretty sure we should adjust them. They get adjusted on
> every active slave change, this is no different. In fact I'd argue that it's a long
> standing bug because they don't get adjusted when the active slave is cleared
> manually and if a new one is chosen (we call bond_select_active_slave() right after)
> then the old one would still have them set. During normal operations and automatic
> curr active slave changes, it is always adjusted.

OK, I rechecked the code. The mcast resend only happens when there is a new
new_active or in rr mode. But bond_option_active_slave_set() only called with
active-backup/alb/tlb mode. So this should be safe.

Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>