From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpo75.interia.pl (smtpo75.interia.pl [217.74.67.75]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6C9303939B9 for ; Fri, 24 Jul 2026 06:52:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.74.67.75 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784875942; cv=none; b=NLpJSBE05vhWw0Ucpv3K3oQESeh82QRA8wGzoH6IktlXZm49hR0OZRH8VoxlN1kjA+k+eqSoV7i/A2q9qBDyzV/h03QlzdO97+O0CRcZuRsJV9pqu9b2bwNA08Tgl+gEv6mT3PugIGQ//jVG9QS54jeoWN68FfHb3QCp1rtyNyI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784875942; c=relaxed/simple; bh=Cq2j6nCsG1W9YHy6Es6QD3t5KZFnZu4TP62QK/ukNQg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pZaMDdfZsn9KkmvPl9xGtvBt6hcsd8a38d119aiUZDZULIeGMUF/9AvsgI/XOVk13XDN5268vUbNwQsw6NY3q1vdRWW5mBSWzR063i65B2s9xz5rz8cD3UeGBuwaPh5gQxx5oR2t4Q/YODk/6QALLeu4kjyTSTAOiwcZwqs0CZg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=poczta.fm; spf=pass smtp.mailfrom=poczta.fm; dkim=pass (1024-bit key) header.d=poczta.fm header.i=@poczta.fm header.b=tqfx5bxW; arc=none smtp.client-ip=217.74.67.75 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=poczta.fm Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=poczta.fm Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=poczta.fm header.i=@poczta.fm header.b="tqfx5bxW" Received: from nr200 (unknown [80.68.231.31]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by poczta.interia.pl (INTERIA.PL) with ESMTPSA; Fri, 24 Jul 2026 08:50:40 +0200 (CEST) Date: Fri, 24 Jul 2026 08:50:38 +0200 From: Slawomir Stepien To: Johannes Berg Cc: syzbot , syzkaller-bugs@googlegroups.com, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot@lists.linux.dev Subject: Re: [PATCH] wifi: mac80211: reject station association if AP is not started Message-ID: References: <373210a9-4365-4cac-823a-0eec391858e7@mail.kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=poczta.fm; s=dk; t=1784875842; bh=HaUyiyeVE8/D8M/2JyJH7aoOIeDgF0ROU13rB91Bv7w=; h=Date:From:To:Subject:Message-ID:MIME-Version:Content-Type; b=tqfx5bxWFjmLF7gFIMSPUjc73EyYTmVddwyTlJuo1y1TLj5ybofbY7sfxDji2znUS U0Oy1O2FYBguvXhG7qqBcCdPk+1Xd0B2cfFBaID6Vew9HKawB88hRB+s8xL0+5RVvj 484WK87Cc0fEcWrzkHhYCl60RolfngK6+Rp88x6o= On lip 23, 2026 11:14, Johannes Berg wrote: > On Thu, 2026-07-23 at 08:11 +0000, syzbot wrote: > > From: Slawomir Stepien > > I'm a bit confused? Did syzbot just pick up another patch? Hi Johannes! No, this issue has been found by syzbot while doing fuzzing testing. > > dereferences the NULL chanctx_conf, triggering a WARN_ON: > > That can't be right? Yeah, right. I will rephrase it in v2. > > Fix this by rejecting the addition or modification of a station to the > > associated state if the AP has not been started (chanctx_conf is NULL). > > That's a proxy for "AP is started", but not a good one, I think we > actually have a flag or so somewhere? Maybe even reject it in cfg80211? I haven't seen a good place for rejection, but let me double check. > > Exempt Multi-Link Operation (MLO) interfaces from this check, as they > > handle chanctx_conf per-link rather than globally on the VIF. > > Feels like that's only necessary because the proxy is bad. > > Also maybe a similar issue arises if an MLO AP is only half-started, and > stations are added to all links, or so? Not sure about MLO, but your suggestion sounds logical and such case might be the same as this one. I will take a look at this too. -- Slawomir Stepien