From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH RFC v3 5/5] tpm2: expose resource manager via a device link /dev/tpms Date: Sat, 21 Jan 2017 12:38:56 -0800 Message-ID: <1485031136.26703.16.camel@HansenPartnership.com> References: <20170116131215.28930-1-jarkko.sakkinen@linux.intel.com> <20170116131215.28930-6-jarkko.sakkinen@linux.intel.com> <1484751663.2717.10.camel@HansenPartnership.com> <20170119104922.vhgz4rxw6yzdrxqt@intel.com> <1484828380.3140.11.camel@HansenPartnership.com> <20170120133914.2wk43nteh2hh7n3c@intel.com> <20170120210522.glx4y4oui36oimld@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170120210522.glx4y4oui36oimld-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Jarkko Sakkinen Cc: linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, open list List-Id: tpmdd-devel@lists.sourceforge.net On Fri, 2017-01-20 at 23:05 +0200, Jarkko Sakkinen wrote: > On Fri, Jan 20, 2017 at 03:39:14PM +0200, Jarkko Sakkinen wrote: > > On Thu, Jan 19, 2017 at 07:19:40AM -0500, James Bottomley wrote: > > > On Thu, 2017-01-19 at 12:49 +0200, Jarkko Sakkinen wrote: > > > > On Wed, Jan 18, 2017 at 10:01:03AM -0500, James Bottomley > > > > wrote: > > > > > On Mon, 2017-01-16 at 15:12 +0200, Jarkko Sakkinen wrote: > > > > > > From: James Bottomley < > > > > > > James.Bottomley-d9PhHud1JfjCXq6kfMZ53/egYHeGw8Jk@public.gmane.org> > > > > > > > > > > > > Currently the Resource Manager (RM) is not exposed to > > > > > > userspace. > > > > > > Make this exposure via a separate device, which can now be > > > > > > opened multiple times because each read/write transaction > > > > > > goes > > > > > > separately via the RM. > > > > > > > > > > > > Concurrency is protected by the chip->tpm_mutex for each > > > > > > read/write transaction separately. The TPM is cleared of > > > > > > all > > > > > > transient objects by the time the mutex is dropped, so > > > > > > there > > > > > > should be no interference between the kernel and userspace. > > > > > > > > > > There's actually a missing kfree of context_buf on the > > > > > tpms_release > > > > > path as well. This patch fixes it up. > > > > > > > > Can you send me a fresh version of the whole patch so that I > > > > can > > > > include to v4 that includes also changes that I requested in my > > > > recent comments + all the fixes? > > > > > > Sure, I think the attached is basically it > > > > > > James > > > > Thank you! > > 'tabrm4' branch has been now rebased. It's now on top of master > branch that contains Stefan's latest patch (min body length check) > that I've reviewed and tested. It also contains your updated > /dev/tpms patch. > > I guess the 5 commits that are there now are such that we have fairly > good consensus, don't we? If so, can I add your reviewed-by and > tested-by to my commits and vice versa? It looks like there's another problem: you need a continue after the transient object is garbage collected otherwise the code falls through, does a flush which fails and then adds a ~0 as the handle meaning we'll have a mismatch between the saved contexts and the handles. James --- commit 0da3f83ce889379bd1741a11b07a30818a223924 Author: James Bottomley Date: Sat Jan 21 12:19:06 2017 -0800 continue after lazy reclaim diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c index 8713d7f..9d87537 100644 --- a/drivers/char/tpm/tpm2-space.c +++ b/drivers/char/tpm/tpm2-space.c @@ -288,9 +288,10 @@ static int tpm2_save_space(struct tpm_chip *chip) rc = tpm2_save_context(chip, space->context_tbl[i], space->context_buf, PAGE_SIZE, &offset); - if (rc == -ENOENT) + if (rc == -ENOENT) { space->context_tbl[i] = 0; - else if (rc) { + continue; + } else if (rc) { tpm2_flush_space(chip); return rc; } ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751433AbdAUUqW (ORCPT ); Sat, 21 Jan 2017 15:46:22 -0500 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:41456 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750817AbdAUUqO (ORCPT ); Sat, 21 Jan 2017 15:46:14 -0500 Message-ID: <1485031136.26703.16.camel@HansenPartnership.com> Subject: Re: [tpmdd-devel] [PATCH RFC v3 5/5] tpm2: expose resource manager via a device link /dev/tpms From: James Bottomley To: Jarkko Sakkinen Cc: linux-security-module@vger.kernel.org, tpmdd-devel@lists.sourceforge.net, open list Date: Sat, 21 Jan 2017 12:38:56 -0800 In-Reply-To: <20170120210522.glx4y4oui36oimld@intel.com> References: <20170116131215.28930-1-jarkko.sakkinen@linux.intel.com> <20170116131215.28930-6-jarkko.sakkinen@linux.intel.com> <1484751663.2717.10.camel@HansenPartnership.com> <20170119104922.vhgz4rxw6yzdrxqt@intel.com> <1484828380.3140.11.camel@HansenPartnership.com> <20170120133914.2wk43nteh2hh7n3c@intel.com> <20170120210522.glx4y4oui36oimld@intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2017-01-20 at 23:05 +0200, Jarkko Sakkinen wrote: > On Fri, Jan 20, 2017 at 03:39:14PM +0200, Jarkko Sakkinen wrote: > > On Thu, Jan 19, 2017 at 07:19:40AM -0500, James Bottomley wrote: > > > On Thu, 2017-01-19 at 12:49 +0200, Jarkko Sakkinen wrote: > > > > On Wed, Jan 18, 2017 at 10:01:03AM -0500, James Bottomley > > > > wrote: > > > > > On Mon, 2017-01-16 at 15:12 +0200, Jarkko Sakkinen wrote: > > > > > > From: James Bottomley < > > > > > > James.Bottomley@HansenPartnership.com> > > > > > > > > > > > > Currently the Resource Manager (RM) is not exposed to > > > > > > userspace. > > > > > > Make this exposure via a separate device, which can now be > > > > > > opened multiple times because each read/write transaction > > > > > > goes > > > > > > separately via the RM. > > > > > > > > > > > > Concurrency is protected by the chip->tpm_mutex for each > > > > > > read/write transaction separately. The TPM is cleared of > > > > > > all > > > > > > transient objects by the time the mutex is dropped, so > > > > > > there > > > > > > should be no interference between the kernel and userspace. > > > > > > > > > > There's actually a missing kfree of context_buf on the > > > > > tpms_release > > > > > path as well. This patch fixes it up. > > > > > > > > Can you send me a fresh version of the whole patch so that I > > > > can > > > > include to v4 that includes also changes that I requested in my > > > > recent comments + all the fixes? > > > > > > Sure, I think the attached is basically it > > > > > > James > > > > Thank you! > > 'tabrm4' branch has been now rebased. It's now on top of master > branch that contains Stefan's latest patch (min body length check) > that I've reviewed and tested. It also contains your updated > /dev/tpms patch. > > I guess the 5 commits that are there now are such that we have fairly > good consensus, don't we? If so, can I add your reviewed-by and > tested-by to my commits and vice versa? It looks like there's another problem: you need a continue after the transient object is garbage collected otherwise the code falls through, does a flush which fails and then adds a ~0 as the handle meaning we'll have a mismatch between the saved contexts and the handles. James --- commit 0da3f83ce889379bd1741a11b07a30818a223924 Author: James Bottomley Date: Sat Jan 21 12:19:06 2017 -0800 continue after lazy reclaim diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c index 8713d7f..9d87537 100644 --- a/drivers/char/tpm/tpm2-space.c +++ b/drivers/char/tpm/tpm2-space.c @@ -288,9 +288,10 @@ static int tpm2_save_space(struct tpm_chip *chip) rc = tpm2_save_context(chip, space->context_tbl[i], space->context_buf, PAGE_SIZE, &offset); - if (rc == -ENOENT) + if (rc == -ENOENT) { space->context_tbl[i] = 0; - else if (rc) { + continue; + } else if (rc) { tpm2_flush_space(chip); return rc; }