Message-ID: <9a3f1cf7577caa808e42092c5fc69c54bf3abe36.camel@sipsolutions.net>
Subject: Re: Kernel oops / WiFi connection failure with wpa_supplicant 2.7
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Arend Van Spriel <arend.vanspriel@broadcom.com>,
        Denis Kenzior <denkenz@gmail.com>, Jouni Malinen <j@w1.fi>,
        Eric Blau <eblau@eblau.com>
Cc:     hostap@lists.infradead.org,
        linux-wireless <linux-wireless@vger.kernel.org>
Date:   Tue, 15 Jan 2019 14:00:21 +0100
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> > Maybe this is a question for Johannes as well, but define 'user-space 
> > applications'?  If that includes wpa_s, wasn't the rule of thumb broken 
> > with that commit?
> 
> In my previous reply I wanted to add that it would be hard to proof that 
> no user-space applications are using the API. Not sure exactly when 
> things were added in wpa_s, but I suspect it was 
> post-commit-503c1fb98ba3 so it did not have support for the user-space 
> API before the commit.

I don't know about this really.

My thought at the time likely was that if there's no driver implementing
it, no userspace could've existed? Or maybe that just wasn't true, and I
got confused?

In any case, it certainly wasn't an intentional API break.

> > > > - What happens if userspace does send an EAPoL-Start in the middle of 
> > > > an offloaded 4-way handshake?
> > > 
> > > Probably those would be dropped.
> > > 
> > 
> > I would love to have something more definitive than 'Probably', and it 
> > might be worth mentioning this hint in the documentation somewhere.
> 
> I was hesitant to use that word, but decided to do so simply because I 
> can not speak for every driver and even for the brcmfmac driver that I 
> maintain I will need to look into the firmware to be sure. I agree that 
> a remark of that possibility is worth adding.

I don't really know if we should really cover all possible error
scenarios like that?

johannes