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From:   Kees Cook <keescook@chromium.org>
Date:   Mon, 8 Apr 2019 08:02:51 -0700
Message-ID: <CAGXu5jL8ijV8AXLeeakvP7iXeYGSgyVWOUw+Mp_M0oxL7jf0ZA@mail.gmail.com>
Subject: Re: [REGRESSION] AppArmor module parameter layout changed with c5459b829b716
To:     David Rheinsberg <david.rheinsberg@gmail.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        John Johansen <john.johansen@canonical.com>,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        linux-security-module <linux-security-module@vger.kernel.org>,
        Casey Schaufler <casey@schaufler-ca.com>
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On Mon, Apr 8, 2019 at 12:21 AM David Rheinsberg
<david.rheinsberg@gmail.com> wrote:
>
> Hi
>
> A recent commit changed how `/sys/module/apparmor/parameters/enabled`
> looks. It was "Y"/"N" before, now it is an integer. I *think* the
> commit that changed this was:

Oooh... the _output_ appears differently based on the type. Argh. Let
me work something up...

> commit c5459b829b716dafd226ad270f25c9a3050f7586
> Author: Kees Cook <keescook@chromium.org>
> Date:   Thu Sep 13 22:28:48 2018 -0700
>
>     LSM: Plumb visibility into optional "enabled" state
>
> I haven't recompiled with a revert, but changing the module-parameter
> type looks like the obvious culprit. I don't see how this change can
> be safe?
>
> This breaks the AppArmor detection of `dbus-broker`. Can the commit be reverted?

Thanks for catching this!

-- 
Kees Cook