Received-SPF: pass (google.com: domain of linux-nfs+bounces-1841-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
Date: Wed, 07 Feb 2024 22:18:42 -0500
Message-ID: <a2ad49e279b2904385064e4d0f65f0ab@paul-moore.com>
Precedence: bulk
MIME-Version: 1.0 
Content-Type: text/plain; charset=utf-8 
Content-Disposition: inline 
Content-Transfer-Encoding: 8bit
From: Paul Moore <paul@paul-moore.com>
To: Roberto Sassu <roberto.sassu@huaweicloud.com>, viro@zeniv.linux.org.uk, brauner@kernel.org, chuck.lever@oracle.com, jlayton@kernel.org, neilb@suse.de, kolga@netapp.com, Dai.Ngo@oracle.com, tom@talpey.com, jmorris@namei.org, serge@hallyn.com, zohar@linux.ibm.com, dmitry.kasatkin@gmail.com, eric.snowberg@oracle.com, dhowells@redhat.com, jarkko@kernel.org, stephen.smalley.work@gmail.com, eparis@parisplace.org, casey@schaufler-ca.com, shuah@kernel.org, mic@digikod.net
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-security-module@vger.kernel.org, linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, selinux@vger.kernel.org, linux-kselftest@vger.kernel.org, Roberto Sassu <roberto.sassu@huawei.com>, Stefan Berger <stefanb@linux.ibm.com>
Subject: Re: [PATCH v9 11/25] security: Introduce inode_post_removexattr hook
References: <20240115181809.885385-12-roberto.sassu@huaweicloud.com>
In-Reply-To: <20240115181809.885385-12-roberto.sassu@huaweicloud.com>

On Jan 15, 2024 Roberto Sassu <roberto.sassu@huaweicloud.com> wrote:
> 
> In preparation for moving IMA and EVM to the LSM infrastructure, introduce
> the inode_post_removexattr hook.
> 
> At inode_removexattr hook, EVM verifies the file's existing HMAC value. At
> inode_post_removexattr, EVM re-calculates the file's HMAC with the passed
> xattr removed and other file metadata.
> 
> Other LSMs could similarly take some action after successful xattr removal.
> 
> The new hook cannot return an error and cannot cause the operation to be
> reverted.
> 
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
> ---
>  fs/xattr.c                    |  9 +++++----
>  include/linux/lsm_hook_defs.h |  2 ++
>  include/linux/security.h      |  5 +++++
>  security/security.c           | 14 ++++++++++++++
>  4 files changed, 26 insertions(+), 4 deletions(-)

Acked-by: Paul Moore <paul@paul-moore.com>

--
paul-moore.com