Received-SPF: pass (google.com: domain of linux-nfs-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <cbd61b82-43e1-ad4d-e984-775f1209948c@schaufler-ca.com>
Date:   Wed, 31 May 2023 07:17:08 -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 -next 0/2] lsm: Change inode_setattr() to take struct
Content-Language: en-US
To:     Christoph Hellwig <hch@lst.de>
Cc:     Christian Brauner <brauner@kernel.org>,
        =?UTF-8?B?TWlja2HDq2wgU2FsYcO8?= =?UTF-8?Q?n?= <mic@digikod.net>,
        Xiu Jianfeng <xiujianfeng@huawei.com>,
        gregkh@linuxfoundation.org, rafael@kernel.org,
        viro@zeniv.linux.org.uk, dhowells@redhat.com, code@tyhicks.com,
        hirofumi@mail.parknet.co.jp, linkinjeon@kernel.org,
        sfrench@samba.org, senozhatsky@chromium.org, tom@talpey.com,
        chuck.lever@oracle.com, jlayton@kernel.org, miklos@szeredi.hu,
        paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com,
        stephen.smalley.work@gmail.com, eparis@parisplace.org,
        dchinner@redhat.com, john.johansen@canonical.com,
        mcgrof@kernel.org, mortonm@chromium.org, fred@cloudflare.com,
        mpe@ellerman.id.au, nathanl@linux.ibm.com, gnoack3000@gmail.com,
        roberto.sassu@huawei.com, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-cachefs@redhat.com,
        ecryptfs@vger.kernel.org, linux-cifs@vger.kernel.org,
        linux-nfs@vger.kernel.org, linux-unionfs@vger.kernel.org,
        linux-security-module@vger.kernel.org, selinux@vger.kernel.org,
        wangweiyang2@huawei.com, Casey Schaufler <casey@schaufler-ca.com>
References: <20230505081200.254449-1-xiujianfeng@huawei.com>
 <20230515-nutzen-umgekehrt-eee629a0101e@brauner>
 <75b4746d-d41e-7c9f-4bb0-42a46bda7f17@digikod.net>
 <20230530-mietfrei-zynisch-8b63a8566f66@brauner>
 <20230530142826.GA9376@lst.de>
 <301a58de-e03f-02fd-57c5-1267876eb2df@schaufler-ca.com>
 <20230531132200.GB30016@lst.de>
From:   Casey Schaufler <casey@schaufler-ca.com>
In-Reply-To: <20230531132200.GB30016@lst.de>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 5/31/2023 6:22 AM, Christoph Hellwig wrote:
> On Tue, May 30, 2023 at 07:55:17AM -0700, Casey Schaufler wrote:
>> Which LSM(s) do you think ought to be deprecated?
> I have no idea.  But what I want is less weirdo things messing with
> VFS semantics.

I am curious what you consider a weirdo thing done by LSMs. Things like
io_uring are much stranger than anything an LSM does.

>
>> I only see one that I
>> might consider a candidate. As for weird behavior, that's what LSMs are
>> for, and the really weird ones proposed (e.g. pathname character set limitations)
>> (and excepting for BPF, of course) haven't gotten far.
> They haven't gotten far for a reason usually.  Trying to sneak things in
> through the back door is exactly what is the problem with LSMs.

Mostly developers play by the rules, and we don't let things sneak in.