From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.w1.fi (mail.w1.fi [212.71.239.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A7E4E1E0DB3; Mon, 3 Feb 2025 10:48:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.71.239.96 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738579726; cv=none; b=eT0Jl0zxO5dvOgfBSCRnHdol9l1CYdHwowrE8UH6EhKXw5D6BgVqM7gZH/mvPow81+ei1GgBL9tzU0Ox5oZ3Nl3tqRIFQHBRqiPufxBe+OobzsrMhnq+7AcNpBUnF2ZiT/5bqVWI0MZWXmi9R4zshcQkl1M6J6XomBXrNO6LzNs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738579726; c=relaxed/simple; bh=sekvpPexvmQdy0Fo/779D+igUWcBh5Z432CGAD709/4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HqsskBe6KOf34XW9ju+uSHiAgeiZBgC+dGpSdPzOUZHlS7gHKgVFhKU1ej1RcmIDtKcllpxEdCWJD5hheusAZH1uIbrYyh4P9OPE7Z9ZFjPcrcORNccYT2cGxUbbGCae/wNpzdLKZ/ylGGYBiw0piMAeXkQqlYSudNNhV9UMf8Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=w1.fi; spf=pass smtp.mailfrom=w1.fi; dkim=pass (2048-bit key) header.d=w1.fi header.i=@w1.fi header.b=l4bcrekQ; arc=none smtp.client-ip=212.71.239.96 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=w1.fi Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=w1.fi Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=w1.fi header.i=@w1.fi header.b="l4bcrekQ" Received: from localhost (localhost [127.0.0.1]) by mail.w1.fi (Postfix) with ESMTP id C893B11C71; Mon, 3 Feb 2025 10:40:51 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at w1.fi Received: from mail.w1.fi ([127.0.0.1]) by localhost (mail.w1.fi [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 2RbUdEjGWDZt; Mon, 3 Feb 2025 10:40:28 +0000 (UTC) Received: by jm (sSMTP sendmail emulation); Mon, 03 Feb 2025 12:40:26 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=w1.fi; s=default; t=1738579228; bh=sekvpPexvmQdy0Fo/779D+igUWcBh5Z432CGAD709/4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=l4bcrekQPWct+AGMZbOjcLHUDG387g3wQunDTgva3o8//qiTDLefZnCqPAbX2YQ5R 44QmJWCG6RrK5NB9pShdZz5d7QPIOidVzunxcVpN52FUiuQGqoms2S2TQyoMU1sC3b /BJu8FWvllimcEfK8YLT+Fa7pKtbiQkUk5oB6CpRAH1fKanojGX3Qx1hnf+Yz0HAzi Qor1X2k96QI57j0EqPKKuKLHrQrd7lriu3AFKAI7VB5L1emx68wECNmKhj+NlnyLZ4 qolaL311IMIa/JAO7XfEashgnw0lAt6XkJRp9cy7lMBmjm6ss7JPm+VYEvEXM5BFaL VlPgvbhH9TjTg== Date: Mon, 3 Feb 2025 12:40:26 +0200 From: Jouni Malinen To: Johannes Berg Cc: Fedor Pchelkin , Vitaliy Shevtsov , lvc-project@linuxtesting.org, Michael Wu , linux-wireless@vger.kernel.org, "John W. Linville" , linux-kernel@vger.kernel.org, syzbot+2e5c1e55b9e5c28a3da7@syzkaller.appspotmail.com Subject: Re: [lvc-project] [PATCH] wifi: nl80211: override all other flags if MONITOR_FLAG_COOK_FRAMES is set Message-ID: References: <20250130123432.4534-1-v.shevtsov@mt-integration.ru> <14c5edc71a74049c49d51960249b0aefc77208be.camel@sipsolutions.net> <49fe46c6a158873cdc6593b0d5630b62a59ed059.camel@sipsolutions.net> 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: <49fe46c6a158873cdc6593b0d5630b62a59ed059.camel@sipsolutions.net> On Thu, Jan 30, 2025 at 10:13:14PM +0100, Johannes Berg wrote: > On Thu, 2025-01-30 at 22:23 +0300, Fedor Pchelkin wrote: > > Wouldn't it break existing userspace, especially in context of systems > > running old stable kernels where the patch is also needed? > > > > There is still some usage of this flag in hostap [1]. > > Theoretically, but I just commented on that here: > > https://lore.kernel.org/r/a49e58998553c45953a30243ad1957c06ce6db8c.camel@sipsolutions.net > > tl;dr: only ancient hostapd versions will actually _use_ it, and they > have to fall into a relatively narrow range (April 2009 - Dec 2011.) How did you determine that commit a11241fa1149 ("nl80211: Use nl80211 for mgmt TX/RX in AP mode") ends this use? Support for monitor mode interface is still in hostap.git and it is even tested as part of the hwsim test cases.. Both hostapd and wpa_supplicant can still be configured to use the monitor interface. It would be another question to ask whether there is any good reason to use this anymore now that a better approach has been available for 13 years and the answer to that is likely "no". Anyway, this is a kernel interface that has a user even in the current snapshot of user space programs. If we are about to break that use, it would make sense to first remove such users. I don't think I would really care about this anymore and it would be nice to get rid of all that unlikely to be used much, if at all, code. > > Or your suggestion is to explicitly reject setting MONITOR_FLAG_COOK_FRAMES > > only when it is passed combined with some other flags which it is > > incompatible with? > > Yes. Though, this seems to imply that the case used by hostapd/wpa_supplicant would not be broken. -- Jouni Malinen PGP id EFC895FA