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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Fri, 11 Oct 2019 14:00:50 -0700
Message-ID: <CAHk-=wiGtEDhwJab7+tQzmjDssynBruRvgj9NJY2bzNrVzw+0Q@mail.gmail.com>
Subject: Re: [PATCH] tracefs: Do not allocate and free proxy_ops for lockdown
To:     Steven Rostedt <rostedt@goodmis.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>,
        Ben Hutchings <ben@decadent.org.uk>,
        Al Viro <viro@zeniv.linux.org.uk>
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On Fri, Oct 11, 2019 at 1:55 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> I guess I can keep it this way. Thoughts?

That looks fine to me. I'm still not sure you actually need to do all
this, but it doesn't look _wrong_.

That said, I still do think that if things are locked down from the
very get-go, tracefs_create_file() shouldn't even create the files.

That's mostly an independent thing from the "what about if they exists
and things got locked down afterwards", though.

I do wonder about the whole "well, if you started tracing before
locking things down, don't you want to see the end results"?

             Linus