Re: [PATCH] cfg80211: inspect off channel operation only when off channel given

[Johannes Berg <johannes@sipsolutions.net>]

On Fri, 2018-07-06 at 14:31 +0200, Johannes Berg wrote:
> On Tue, 2018-07-03 at 16:04 -0700, peter.oh@bowerswilkins.com wrote:
> > From: Peter Oh <peter.oh@bowerswilkins.com>
> > 
> > NL80211_ATTR_OFFCHANNEL_TX_OK does not mean given channel is always
> > off channel, but it means the channel given could be off channel.
> > Hence it should not block the given channel to be used if given
> > channel does not require off channel mgmt tx although regulatory
> > domain is non-ETSI.
> > 
> > Signed-off-by: Peter Oh <peter.oh@bowerswilkins.com>
> > ---
> >  net/wireless/nl80211.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
> > index 4eece06..991042b 100644
> > --- a/net/wireless/nl80211.c
> > +++ b/net/wireless/nl80211.c
> > @@ -9915,7 +9915,9 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info)
> >  		return -EINVAL;
> >  
> >  	wdev_lock(wdev);
> > -	if (params.offchan && !cfg80211_off_channel_oper_allowed(wdev)) {
> > +	if (params.offchan &&
> > +	    !cfg80211_chandef_identical(&chandef, &wdev->chandef) &&
> > +	    !cfg80211_off_channel_oper_allowed(wdev)) {
> >  		wdev_unlock(wdev);
> 
> Hmm. That seems fine, but can we be sure that wdev->chandef is always
> valid? ISTR that it isn't necessarily updated all the time, but I can't
> really say right now.

For the record, in addition to this question, the commit log might need
some rewording since the whole regulatory/non-ETSI part isn't really
obvious (and not clear to me right now).

I've had this patch waiting for about a year now, I'll drop it. Please
resend if it's still relevant.

johannes