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Message-ID: <f20e7ff3c6c3aa445faa01d12800a9675a77f102.camel@linux.ibm.com>
Subject: Re: [PATCH v4 3/5] security: Allow all LSMs to provide xattrs for
 inode_init_security hook
From:   Mimi Zohar <zohar@linux.ibm.com>
To:     Roberto Sassu <roberto.sassu@huaweicloud.com>,
        Casey Schaufler <casey@schaufler-ca.com>,
        dmitry.kasatkin@gmail.com, paul@paul-moore.com, jmorris@namei.org,
        serge@hallyn.com, stephen.smalley.work@gmail.com,
        eparis@parisplace.org
Cc:     linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org, selinux@vger.kernel.org,
        reiserfs-devel@vger.kernel.org, linux-kernel@vger.kernel.org,
        keescook@chromium.org, nicolas.bouchinet@clip-os.org,
        Roberto Sassu <roberto.sassu@huawei.com>
Date:   Fri, 18 Nov 2022 10:33:19 -0500
In-Reply-To: <2e493258-b267-b8ad-0812-53f4e9c849ae@huaweicloud.com>
References: <20221110094639.3086409-1-roberto.sassu@huaweicloud.com>
         <20221110094639.3086409-4-roberto.sassu@huaweicloud.com>
         <4c1349f670dc3c23214a5a5036e43ddaa0a7bc89.camel@linux.ibm.com>
         <026075fa-0b58-9041-0727-b75e19499356@schaufler-ca.com>
         <2e493258-b267-b8ad-0812-53f4e9c849ae@huaweicloud.com>
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On Fri, 2022-11-18 at 10:32 +0100, Roberto Sassu wrote:
> > Smack uses multiple xattrs. All file system objects have a SMACK64
> > attribute, which is used for access control. A program file may have
> > a SMACK64EXEC attribute, which is the label the program will run with.
> > A library may have a SMACK64MMAP attribute to restrict loading. A
> > directory may have a SMACK64TRANSMUTE attribute, which modifies the
> > new object creation behavior.
> > 
> > The point being that it may be more than a "nice idea" to support
> > multiple xattrs. It's not a hypothetical situation.
> 
> Ok, that means that I have to change the number of xattrs reserved by 
> Smack in patch 3.

Based on evm_config_default_xattrnames[], there are 4.  There's the
original SMACK and these 3 additional ones.

Mimi