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;
Message-ID: <0a2b8372-11f6-56a3-7d8e-41e93d1bf691@schaufler-ca.com>
Date:   Wed, 31 May 2023 14:36:27 -0700
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101
 Thunderbird/102.11.0
Subject: Re: [PATCH] LSM: Infrastructure management of the sock
Content-Language: en-US
To:     Paul Moore <paul@paul-moore.com>
Cc:     "GONG, Ruiqi" <gongruiqi@huaweicloud.com>,
        John Johansen <john.johansen@canonical.com>,
        James Morris <jmorris@namei.org>,
        "Serge E . Hallyn" <serge@hallyn.com>,
        Stephen Smalley <stephen.smalley.work@gmail.com>,
        Eric Paris <eparis@parisplace.org>,
        linux-kernel@vger.kernel.org, apparmor@lists.ubuntu.com,
        linux-security-module@vger.kernel.org, selinux@vger.kernel.org,
        Kees Cook <keescook@chromium.org>,
        Wang Weiyang <wangweiyang2@huawei.com>,
        Xiu Jianfeng <xiujianfeng@huawei.com>, gongruiqi1@huawei.com,
        Casey Schaufler <casey@schaufler-ca.com>
References: <20230531110506.142951-1-gongruiqi@huaweicloud.com>
 <fe6a0f1e-6378-a4f2-f995-46799ed5248e@schaufler-ca.com>
 <CAHC9VhQHUKXLejiMvETYE_PJz3cyHPF5z+T1ifUCD9ezMztcSQ@mail.gmail.com>
From:   Casey Schaufler <casey@schaufler-ca.com>
In-Reply-To: <CAHC9VhQHUKXLejiMvETYE_PJz3cyHPF5z+T1ifUCD9ezMztcSQ@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

On 5/31/2023 2:10 PM, Paul Moore wrote:
> On Wed, May 31, 2023 at 10:00 AM Casey Schaufler <casey@schaufler-ca.com> wrote:
>> On 5/31/2023 4:05 AM, GONG, Ruiqi wrote:
>>> As the security infrastructure has taken over the management of multiple
>>> *_security blobs that are accessed by multiple security modules, and
>>> sk->sk_security shares the same situation, move its management out of
>>> individual security modules and into the security infrastructure as
>>> well. The infrastructure does the memory allocation, and each relavant
>>> module uses its own share.
>> Do you have a reason to make this change? The LSM infrastructure
>> manages other security blobs to enable multiple concurrently active
>> LSMs to use the blob. If only one LSM on a system can use the
>> socket blob there's no reason to move the management.
> I think an argument could be made for consistent handling of security
> blobs, but with the LSM stacking work in development the argument for
> merging this patch needs to be a lot stronger than just "consistency".

I'm betting that someone has an out-of-tree LSM that uses a socket blob,
and that the intended use case includes stacking with one of the "major"
LSMs. I would encourage that someone to propose that LSM for upstream.