Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20230331123221.3273328-1-roberto.sassu@huaweicloud.com> <20230331123221.3273328-4-roberto.sassu@huaweicloud.com>
In-Reply-To: <20230331123221.3273328-4-roberto.sassu@huaweicloud.com>
From:   Paul Moore <paul@paul-moore.com>
Date:   Tue, 4 Apr 2023 14:56:17 -0400
Message-ID: <CAHC9VhSMdrPP6+9cmhAU1=tDikJ5Y8_mJEORdqiaJw3pQuFDDg@mail.gmail.com>
Subject: Re: [PATCH v10 3/4] evm: Align evm_inode_init_security() definition
 with LSM infrastructure
To:     Roberto Sassu <roberto.sassu@huaweicloud.com>
Cc:     zohar@linux.ibm.com, dmitry.kasatkin@gmail.com, jmorris@namei.org,
        serge@hallyn.com, stephen.smalley.work@gmail.com,
        eparis@parisplace.org, casey@schaufler-ca.com,
        reiserfs-devel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org, selinux@vger.kernel.org,
        bpf@vger.kernel.org, kpsingh@kernel.org, keescook@chromium.org,
        nicolas.bouchinet@clip-os.org,
        Roberto Sassu <roberto.sassu@huawei.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

On Fri, Mar 31, 2023 at 8:33=E2=80=AFAM Roberto Sassu
<roberto.sassu@huaweicloud.com> wrote:
>
> From: Roberto Sassu <roberto.sassu@huawei.com>
>
> Change the evm_inode_init_security() definition to align with the LSM
> infrastructure. Keep the existing behavior of including in the HMAC
> calculation only the first xattr provided by LSMs.
>
> Changing the evm_inode_init_security() definition requires passing the
> xattr array allocated by security_inode_init_security(), and the number o=
f
> xattrs filled by previously invoked LSMs.
>
> Use the newly introduced lsm_get_xattr_slot() to position EVM correctly i=
n
> the xattrs array, like a regular LSM, and to increment the number of fill=
ed
> slots. For now, the LSM infrastructure allocates enough xattrs slots to
> store the EVM xattr, without using the reservation mechanism.
>
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> ---
>  include/linux/evm.h               | 13 +++++++------
>  security/integrity/evm/evm_main.c | 16 ++++++++++------
>  security/security.c               |  6 +++---
>  3 files changed, 20 insertions(+), 15 deletions(-)

This seems reasonable to me, but I'll want to see a sign-off from Mimi
for the EVM bits.  Same thing for patch 4/4.

--=20
paul-moore.com