Re: [PATCH] cfg80211: fix sband iftype data lookup for AP_VLAN

[Johannes Berg <johannes@sipsolutions.net>]

On Thu, 2023-06-22 at 18:25 +0200, Felix Fietkau wrote:
> On 22.06.23 18:07, Johannes Berg wrote:
> > On Thu, 2023-06-22 at 18:05 +0200, Felix Fietkau wrote:
> > > Since AP_VLAN interfaces are not pushed to the driver, 
> > > 
> > That's a mac80211 thing though.
> > 
> > > the driver should not
> > > be expected to register iftype data for them.
> > > Map them to the regular AP iftype on lookup.
> > 
> > And this is in cfg80211 - not sure that seems right?
> > 
> > OTOH I'd expect no callers with VLAN here, it doesn't really make sense
> > since they're not a standalone mode that actually has HE/EHT, but still,
> > seems odd this way?
> > 
> > What's actually calling it? I'm guessing somewhere in mac80211?
> 
> Yes, I guess only mac80211 is affected. I put in the cfg80211 prefix
> because that's what the header file belongs to.
> 
> I made the patch in response to this:
> https://patchwork.kernel.org/project/linux-wireless/patch/20230605152141.17434-4-shayne.chen@mediatek.com/

OK, sure, that also doesn't really make sense.

> I found that there are several calls to ieee80211_get_he_iftype_cap and
> ieee80211_get_eht_iftype_cap, which could be affected by this issue.
> I thought dealing with this in a single place would be better than playing
> whac-a-mole by fixing it at the call sites.
> 

I replaced almost all of them with ieee80211_get_he_iftype_cap_vif() so
it shouldn't be that bad? Looks like I forgot some though.

johannes