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Subject: Re: [PATCH bpf-next v8 05/11] seccomp,landlock: Enforce Landlock
 programs per process hierarchy
To:     Andy Lutomirski <luto@kernel.org>,
        Alexei Starovoitov <alexei.starovoitov@gmail.com>
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        LKML <linux-kernel@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
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        Sargun Dhillon <sargun@sargun.me>,
        "Serge E . Hallyn" <serge@hallyn.com>,
        Shuah Khan <shuah@kernel.org>, Tejun Heo <tj@kernel.org>,
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        Will Drewry <wad@chromium.org>,
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        Andrew Morton <akpm@linux-foundation.org>
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From:   Casey Schaufler <casey@schaufler-ca.com>
Message-ID: <b9579dae-625e-cd91-0656-821a8d1f2893@schaufler-ca.com>
Date:   Tue, 27 Feb 2018 09:30:35 -0800
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On 2/27/2018 8:39 AM, Andy Lutomirski wrote:
> On Tue, Feb 27, 2018 at 5:32 AM, Alexei Starovoitov
> <alexei.starovoitov@gmail.com> wrote:
>> [ Snip ]
> An earlier version of the patch set used the seccomp filter chain.
> Mickaël, what exactly was wrong with that approach other than that the
> seccomp() syscall was awkward for you to use?  You could add a
> seccomp_add_landlock_rule() syscall if you needed to.
>
> As a side comment, why is this an LSM at all, let alone a non-stacking
> LSM?  It would make a lot more sense to me to make Landlock depend on
> having LSMs configured in but to call the landlock hooks directly from
> the security_xyz() hooks.

Please, no. It is my serious intention to have at least the
infrastructure blob management in within a release or two, and
I think that's all Landlock needs. The security_xyz() hooks are
sufficiently hackish as it is without unnecessarily adding more
special cases.