Re: [RFC PATCHv3] mac80211: Add support for hardware ARP query filtering

[Johannes Berg <johannes@sipsolutions.net>]

On Thu, 2010-05-27 at 12:05 +0300, Juuso Oikarinen wrote:

> > > +	/* We are concerned about IP addresses only when associated */
> > > +	sdata = IEEE80211_DEV_TO_SUB_IF(ndev);
> > > +	mutex_lock(&sdata->u.mgd.mtx);
> > > +	ifmgd = &sdata->u.mgd;
> > > +	if (ifmgd->associated)
> > > +		ieee80211_set_arp_filter(sdata);
> > > +	mutex_unlock(&sdata->u.mgd.mtx);
> > 
> > I'm sure this will fail in interesting ways since nothing guarantees
> > that this interface is in managed mode.
> 
> S***, I need a vacation. This is bound to fail even if the interface is
> in managed mode, as it's not protecting the right thing. 
> 
> I was already looking at the ifmgd->mtx but somehow managed to
> copy-paste this one :(

Hm? If you bail out on non-managed or something like that, it should be
fine? ifmgd->mtx is the same as sdata->u.mgd.mtx, you just don't need
the ifmgd variable here.

johannes