Return-path: Received: from s3.sipsolutions.net ([144.76.63.242]:55758 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754856AbeEHMTg (ORCPT ); Tue, 8 May 2018 08:19:36 -0400 Message-ID: <1525781970.14830.11.camel@sipsolutions.net> (sfid-20180508_141950_047472_D01128F6) Subject: Re: [PATCH] nl80211: Reject disconnect commands except from conn_owner From: Johannes Berg To: Arend van Spriel , Andrew Zaborowski , Kalle Valo Cc: linux-wireless@vger.kernel.org Date: Tue, 08 May 2018 14:19:30 +0200 In-Reply-To: <5AF1959E.6020605@broadcom.com> (sfid-20180508_141840_870131_A9A1B28D) References: <20180428014732.4018-1-andrew.zaborowski@intel.com> <87in8b8ooy.fsf@purkki.adurom.net> <1525720752.22388.3.camel@sipsolutions.net> <5AF1959E.6020605@broadcom.com> (sfid-20180508_141840_870131_A9A1B28D) Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, 2018-05-08 at 14:18 +0200, Arend van Spriel wrote: > On 5/7/2018 9:19 PM, Johannes Berg wrote: > > On Sun, 2018-04-29 at 20:30 +0200, Andrew Zaborowski wrote: > > > On 28 April 2018 at 15:07, Kalle Valo wrote: > > > > Andrew Zaborowski writes: > > > > > Reject NL80211_CMD_DISCONNECT, NL80211_CMD_DISASSOCIATE, > > > > > NL80211_CMD_DEAUTHENTICATE and NL80211_CMD_ASSOCIATE commands > > > > > from clients other than the connection owner set in the connect, > > > > > authenticate or associate commands, if it was set. > > > > > > > > > > The main point of this check is to prevent chaos when two processes > > > > > try to use nl80211 at the same time, it's not a security measure. > > > > > The same thing should possibly be done for JOIN_IBSS/LEAVE_IBSS and > > > > > START_AP/STOP_AP. > > > > > > > > s-o-b missing. > > > > > > True, thanks. Also I was going to send this as an RFC. > > > > > > > Looks fine to me, please resend if you want it in :) > > Do we really want this? Is the referred chaos hypothetical or an actual > issue. Nothing stops me from doing an 'ifconfig down' so why should 'iw > disconnect' be any different. As far I can tell it does not affect my > testing environment, but particularly in such use-cases I can expect > issues adopting this change, which is also hypothetical of course ;-) Yeah, it's a good question. But it might help with inadvertent issues, like starting wpa_s which immediately disconnects if it finds something connected. If that fails, perhaps you have a better chance of noticing the error? johannes