Re: [REGRESSION] 3.2.0-rc3 Bluetooth L2CAP Linux to Linux rfcommfails

From: Gustavo Padovan
Date: Sun Dec 18 2011 - 19:36:06 EST


Hi David,

* David Fries <david@xxxxxxxxx> [2011-12-10 23:16:24 -0600]:

> On Mon, Oct 31, 2011 at 05:01:29PM -0200, Gustavo Padovan wrote:
> > Hi Arek,
> >
> > * Arek Lichwa <arkadiusz.lichwa@xxxxxxxxx> [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
>
> I just found that I can't connect rfcomm any more from Linux (desktop)
> to Linux (N900) with bluetooth. On the desktop side, 3.2.0-rc2 works,
> but 3.2.0-rc3 (and on) fails, I even merged in
> git://git.kernel.org/pub/scm/linux/kernel/git/padovan/bluetooth-next
> master 5a13b09531420d230616bd524b68a5b0c23cd487 without any change.
> Fortunately there were only three bluetooth patches between rc2 and rc3.
> Reverting 4dff523a913197e3314c7b0d08734ab037709093 fixed the issue and
> I can connect again.

I wen ahead and reverted this one.

Gustavo
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