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Message-ID: <c327ecb762ef788ef248ed5c006eeef5afa3b798.camel@decadent.org.uk>
Subject: Re: [PATCH] tracefs: Do not allocate and free proxy_ops for lockdown
From:   Ben Hutchings <ben@decadent.org.uk>
To:     Steven Rostedt <rostedt@goodmis.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Matthew Garrett <matthewgarrett@google.com>,
        James Morris James Morris <jmorris@namei.org>,
        LSM List <linux-security-module@vger.kernel.org>,
        Linux API <linux-api@vger.kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>
Date:   Fri, 11 Oct 2019 20:50:56 +0100
In-Reply-To: <20191011143610.21bcd9c0@gandalf.local.home>
References: <20191011135458.7399da44@gandalf.local.home>
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         <20191011143610.21bcd9c0@gandalf.local.home>
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On Fri, 2019-10-11 at 14:36 -0400, Steven Rostedt wrote:
> On Fri, 11 Oct 2019 11:20:30 -0700
> Linus Torvalds <torvalds@linux-foundation.org> wrote:
>=20
> > Willing to do that instead?
>=20
> Honestly, what you described was my preferred solution ;-)
>=20
> I just didn't want to upset the lockdown crowd if a new tracefs file
> was opened without doing this.
>=20
> Once locked down is set, can it ever be undone without rebooting?
[...]

Earlier versions of the lockdown patch set added a magic SysRq command
to turn it off.  That's not currently present upstream but there may be
plans to add it.

Ben.

--=20
Ben Hutchings
It is easier to change the specification to fit the program
than vice versa.


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