Re: [PATCH v5 net-next 1/6] net: bridge: add locked entry fdb flag to extend locked port feature

[netdev@xxxxxxxxxxxxxxxxxxxx]

On 2022-08-27 17:19, Ido Schimmel wrote:
> On Fri, Aug 26, 2022 at 01:45:33PM +0200, Hans Schultz wrote:
> >  	nbp_switchdev_frame_mark(p, skb);
> > @@ -943,6 +946,10 @@ static int br_setport(struct net_bridge_port *p, 
> > struct nlattr *tb[],
> >  	br_set_port_flag(p, tb, IFLA_BRPORT_NEIGH_SUPPRESS, 
> > BR_NEIGH_SUPPRESS);
> >  	br_set_port_flag(p, tb, IFLA_BRPORT_ISOLATED, BR_ISOLATED);
> >  	br_set_port_flag(p, tb, IFLA_BRPORT_LOCKED, BR_PORT_LOCKED);
> > +	br_set_port_flag(p, tb, IFLA_BRPORT_MAB, BR_PORT_MAB);
> > +
> > +	if (!(p->flags & BR_PORT_LOCKED))
> > +		p->flags &= ~BR_PORT_MAB;

The reason for this is that I wanted it to be so that if you have MAB 
enabled (and locked of course) and unlock the port, it will 
automatically clear both flags instead of having to first disable MAB 
and then unlock the port.

> Any reason not to emit an error if MAB is enabled while the port is
> unlocked? Something like this (untested):
>
> diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
> index 5aeb3646e74c..18353a4c29e1 100644
> --- a/net/bridge/br_netlink.c
> +++ b/net/bridge/br_netlink.c
> @@ -944,6 +944,12 @@ static int br_setport(struct net_bridge_port *p,
> struct nlattr *tb[],
>         br_set_port_flag(p, tb, IFLA_BRPORT_ISOLATED, BR_ISOLATED);
>         br_set_port_flag(p, tb, IFLA_BRPORT_LOCKED, BR_PORT_LOCKED);
>
> +       if (!(p->flags & BR_PORT_LOCKED) && (p->flags & BR_PORT_MAB)) {
> +               NL_SET_ERR_MSG(extack, "MAB cannot be enabled when
> port is unlocked");
> +               p->flags = old_flags;
> +               return -EINVAL;
> +       }
> +
>         changed_mask = old_flags ^ p->flags;
>
>         err = br_switchdev_set_port_flag(p, p->flags, changed_mask, 
> extack);