Message-ID: <070d4006cd7d0ee1b2cf4e0dd7e4d5c7be2bcb65.camel@huaweicloud.com>
Subject: Re: [PATCH v2] security: Introduce LSM_ORDER_LAST and set it for
 the integrity LSM
From:   Roberto Sassu <roberto.sassu@huaweicloud.com>
To:     Mimi Zohar <zohar@linux.ibm.com>, dmitry.kasatkin@gmail.com,
        paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com
Cc:     linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, keescook@chromium.org,
        Roberto Sassu <roberto.sassu@huawei.com>
Date:   Thu, 09 Mar 2023 08:55:33 +0100
In-Reply-To: <b8ed9f24e051158580c561a8d8863622ba2f4c8e.camel@linux.ibm.com>
References: <20230308171119.1784326-1-roberto.sassu@huaweicloud.com>
         <b8ed9f24e051158580c561a8d8863622ba2f4c8e.camel@linux.ibm.com>
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On Wed, 2023-03-08 at 19:23 -0500, Mimi Zohar wrote:
> On Wed, 2023-03-08 at 18:11 +0100, Roberto Sassu wrote:
> > From: Roberto Sassu <roberto.sassu@huawei.com>
> > 
> > Introduce LSM_ORDER_LAST, to satisfy the requirement of LSMs willing to be
> > the last, e.g. the 'integrity' LSM, without changing the kernel command
> > line or configuration.
> 
> ^needing to be last

Ok.

> > Also, set this order for the 'integrity' LSM. While not enforced, this is
> > the only LSM expected to use it.
> > 
> > Similarly to LSM_ORDER_FIRST, LSMs with LSM_ORDER_LAST are always enabled
> > and put at the end of the LSM list.
> > 
> > Finally, for LSM_ORDER_MUTABLE LSMs, set the found variable to true if an
> > LSM is found, regardless of its order. In this way, the kernel would not
> > wrongly report that the LSM is not built-in in the kernel if its order is
> > LSM_ORDER_LAST.
> > 
> > Fixes: 79f7865d844c ("LSM: Introduce "lsm=" for boottime LSM selection")
> > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> 
> Thanks, Roberto.  With this patch, 'integrity' can be safely removed
> from CONFIG_LSM definitions.

Perfect, will add the new patch.

Thanks

Roberto