Return-Path: Date: Mon, 7 Nov 2011 16:54:01 -0200 From: Gustavo Padovan To: Arkadiusz.Lichwa@tieto.com Cc: linux-bluetooth@vger.kernel.org, iliak@ti.com, ulrik.lauren@stericsson.com Subject: Re: [PATCH cover letter] Bluetooth: Revert: Fix L2CAP connection ... Message-ID: <20111107185401.GA3707@joana> References: <1319621002-7122-1-git-send-email-arkadiusz.lichwa@tieto.com> <20111031190129.GA10164@joana> <20111104171821.GE6171@joana> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-bluetooth-owner@vger.kernel.org List-ID: * Arkadiusz.Lichwa@tieto.com [2011-11-07 12:06:32 +0200]: > > >From: Gustavo F. Padovan [mailto:pao@profusion.mobi] On Behalf Of Gustavo > >Padovan > >Sent: Friday, November 04, 2011 6:18 PM > >To: Lichwa Arkadiusz > >Cc: linux-bluetooth@vger.kernel.org; iliak@ti.com; ulrik.lauren@stericsson.com > >Subject: Re: [PATCH cover letter] Bluetooth: Revert: Fix L2CAP connection ... > > > >Hi Arek, > > > >* Arkadiusz.Lichwa@tieto.com [2011-11-02 > >09:53:10 +0200]: > > > >> > >> Hi Gustavo > >> > >> >From: Gustavo F. Padovan [mailto:pao@profusion.mobi] On Behalf Of Gustavo > >> >Padovan > >> >Sent: Monday, October 31, 2011 8:01 PM > >> >To: Lichwa Arkadiusz > >> >Cc: linux-bluetooth@vger.kernel.org; iliak@ti.com; ulrik.lauren@stericsson.com > >> >Subject: Re: [PATCH cover letter] Bluetooth: Revert: Fix L2CAP connection ... > >> > > >> >Hi Arek, > >> > > >> >* Arek Lichwa [2011-10-26 11:23:21 +0200]: > >> > > >> >> Hi > >> >> > >> >> We found during testing problem when setting rfcomm (SPP) channel between > >> >> two 2.1 devices. > >> >> The test case always failed mostly saying security block on l2cap level > >> >> but sometimes the fail root cause was 'Command not understood' on l2cap > >> >> as well. > >> >> Analyzing security block issue, I found that there's unencrypted link when > >> >> l2cap command 'connection request' is sent to remote. > >> >> The second issue with 'command not understood' has turn out to be related to > >> >> expiration of l2cap timer and its implications. > >> >> > >> >> Solution that I found to fix the problem seems to be related to old commit > >> >> 330605423ca6eafafb8dcc27502bce1c585d1b06 made by Ilia Kolomisnky. > >When > >> >there's > >> >> authentication ongoing, 'encryption pending' should be turn on, otherwise > >> >> there're situations when link stays unencrypted. > >> >> The issue with timer expiration is related to Andrzej Kaczmarek's patch > >> >> sent to community a couple days ago (~ 2011/10/20). > >> >> This patch actually recalculates (repairs) timer values on l2cap which were > >> >> wrongly converted before. > >> >> With this patch the expiration issue disappears during the test case > >> >> I've made, otherwise just reverting > >> >330605423ca6eafafb8dcc27502bce1c585d1b06 > >> >> is not enough, since timer issue blocks very often passing the test case. > >> > > >> >Are you saying that Andrzej's patch together with revert of 330605423 fixes > >> >the problem? and are you sure that we are not creating any new regression? > >> > > >> > Gustavo > >> > >> Yes, that's right, it fixes. > >> About potencial new regression, I don't think so since previous code before Ilia > >made change was stable and verified. Did you asked Ilia about regression report > >that time? > > > >So did you test this in many different cases? with and without SSP, in all > >security levels, with and without MITM protection and so on? > > Hi Gustavo, > > Should't such scenarios to be run/verified on bluez community's > common security regression test framework/set ? > Looks like now everyone (I hope) verify against his own and it's not trustable. > > To your questions, yes, I did, do you belive me ? :) Ok, I'm applying this one to the bluetooth tree (aka linux 3.2). Thanks. Also I verified the need of this patch while developing the security patches I just sent to the mailing list, it only works if I revert this patch. Gustavo