Received-SPF: pass (google.com: domain of linux-nfs+bounces-822-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249;
Message-ID: <5aa5986266c3a3f834114a835378455cbbff7b64.camel@linux.ibm.com>
Subject: Re: [PATCH v8 23/24] ima: Make it independent from 'integrity' LSM
From: Mimi Zohar <zohar@linux.ibm.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,
        paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com,
        dmitry.kasatkin@gmail.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-fsdevel@vger.kernel.org, linux-kernel@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>
Date: Wed, 27 Dec 2023 08:22:27 -0500
In-Reply-To: <20231214170834.3324559-24-roberto.sassu@huaweicloud.com>
References: <20231214170834.3324559-1-roberto.sassu@huaweicloud.com>
	 <20231214170834.3324559-24-roberto.sassu@huaweicloud.com>
Content-Type: text/plain; charset="ISO-8859-15"
Precedence: bulk
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit

On Thu, 2023-12-14 at 18:08 +0100, Roberto Sassu wrote:
> From: Roberto Sassu <roberto.sassu@huawei.com>
> 
> Make the 'ima' LSM independent from the 'integrity' LSM by introducing IMA
> own integrity metadata (ima_iint_cache structure, with IMA-specific fields
> from the integrity_iint_cache structure), and by managing it directly from
> the 'ima' LSM.
> 
> Move the remaining IMA-specific flags to security/integrity/ima/ima.h,
> since they are now unnecessary in the common integrity layer.
> 
> Replace integrity_iint_cache with ima_iint_cache in various places
> of the IMA code.
> 
> Then, reserve space in the security blob for the entire ima_iint_cache
> structure, so that it is available for all inodes having the security blob
> allocated (those for which security_inode_alloc() was called).  Adjust the
> IMA code accordingly, call ima_iint_inode() to retrieve the ima_iint_cache
> structure. Keep the non-NULL checks since there can be inodes without
> security blob.

Previously the 'iint' memory was only allocated for regular files in
policy and were tagged S_IMA.  This patch totally changes when and how
memory is being allocated.  Does it make sense to allocate memory at
security_inode_alloc()?  Is this change really necessary for making IMA
a full fledged LSM?

Mimi

> 
> Don't include the inode pointer as field in the ima_iint_cache structure,
> since the association with the inode is clear. Since the inode field is
> missing in ima_iint_cache, pass the extra inode parameter to
> ima_get_verity_digest().
> 
> Finally, register ima_inode_alloc_security/ima_inode_free_security() to
> initialize/deinitialize the new ima_iint_cache structure (before this task
> was done by iint_init_always() and iint_free()). Also, duplicate
> iint_lockdep_annotate() for the ima_iint_cache structure, and name it
> ima_iint_lockdep_annotate().
> 
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>