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Date:   Sat, 25 Jan 2020 08:55:23 +1100 (AEDT)
From:   James Morris <jmorris@namei.org>
To:     KP Singh <kpsingh@chromium.org>
cc:     Casey Schaufler <casey@schaufler-ca.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux Security Module list 
        <linux-security-module@vger.kernel.org>, bpf@vger.kernel.org
Subject: Re: [PATCH bpf-next v3 04/10] bpf: lsm: Add mutable hooks list for
 the BPF LSM
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On Thu, 23 Jan 2020, KP Singh wrote:

> 
> > If you want to put mutable hook handling in the infrastructure
> > you need to make it general mutable hook handling as opposed to
> > BPF hook handling. I don't know if that would be acceptable for
> > all the reasons called out about dynamic module loading.
> 
> We can have generic mutable hook handling and if an LSM doesn't
--> provide a mutable security_hook_heads, it would not allow dynamic
> hooks / dynamic module loading.
> 
> So, in practice it will just be the BPF LSM that allows mutable hooks
> and the other existing LSMs won't. I guess it will be cleaner than
> calling the BPF hooks directly from the LSM code (i.e in security.c)

I'm inclined to only have mutable hooks for KRSI, not for all LSMs. This 
is a special case and we don't need to provide this for anyone else.

Btw, folks, PLEASE trim replies.


-- 
James Morris
<jmorris@namei.org>