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Message-ID: <332a5987-8f4e-e26c-cfa5-5121cfa71ba9@schaufler-ca.com>
Date:   Thu, 20 Oct 2022 09:13:33 -0700
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Subject: Re: [PATCH v38 06/39] LSM: lsm_self_attr syscall for LSM self
 attributes
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To:     Paul Moore <paul@paul-moore.com>
Cc:     casey.schaufler@intel.com, linux-security-module@vger.kernel.org,
        linux-audit@redhat.com, jmorris@namei.org, selinux@vger.kernel.org,
        keescook@chromium.org, john.johansen@canonical.com,
        penguin-kernel@i-love.sakura.ne.jp, stephen.smalley.work@gmail.com,
        linux-kernel@vger.kernel.org, casey@schaufler-ca.com
References: <20220927195421.14713-1-casey@schaufler-ca.com>
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From:   Casey Schaufler <casey@schaufler-ca.com>
In-Reply-To: <CAHC9VhQbr1zgyvzM9zB97+rzO-Rcy6CUt_3-54ED-SEanVWyRQ@mail.gmail.com>
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On 10/20/2022 8:44 AM, Paul Moore wrote:
> On Tue, Sep 27, 2022 at 3:57 PM Casey Schaufler <casey@schaufler-ca.com> wrote:
>> Create a system call lsm_self_attr() to provide the security
>> module maintained attributes of the current process. Historically
>> these attributes have been exposed to user space via entries in
>> procfs under /proc/self/attr.
> Hi Casey,
>
> I had hoped to get to review these patches earlier this week, I know
> you are very anxious to see something happen here, but unfortunately
> that didn't work out and I'm now in a position of limited network
> access and time for a bit.  I will do my best to at least comment on
> the new syscall related additions, but thankfully you've already
> started to get some good comments from others so I'm hopeful that will
> help you keep moving forward.

Thanks. I just got back to work myself. Hopefully the comments will prove
useful. I'm just getting to them.

> One comment I did want to make, and it's important: please separate
> the LSM syscall patches from the LSM stacking patches.  While the
> stacking patches will obviously be dependent on the syscall patches,
> the syscall patches should not be dependent on stacking.  However, the
> LSM syscall patches must be designed from the start to support
> multiple, simultaneous LSMs.

OK. I will refactor into two patch sets. The first will be the syscalls
for getting the LSM attributes and the second will be the stacking changes.
The prctl() I proposed to set the "display" LSM will be in the second, as
it makes no sense to have without anything to change. I have not to date
included the SO_PEERCONTEXT that would be required for complete stacking.
Would you like to see that included in the syscall patches?


> Thanks.

Thank you.