Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <20190326182742.16950-1-matthewgarrett@google.com>
 <20190326182742.16950-26-matthewgarrett@google.com> <CALCETrXDF2c2-gnOyNTnEn-uPAZp0AaSB_PB8e2y8jf7zo=Cyg@mail.gmail.com>
 <20190327003057.GA27311@kroah.com> <CALCETrVDDf4dj3Md1Nxc5P_NCToXGnAbEO3bGfwgKSfeVmU4Kw@mail.gmail.com>
 <20190327050615.GA548@kroah.com> <16124107-70D3-4CA0-9766-36FC6DC10128@amacapital.net>
 <20190327053342.GA17484@kroah.com> <CALCETrUW=r=xyr4pGiGnn9zUEevf=z6PP3111Ds6qguV5SjYUQ@mail.gmail.com>
In-Reply-To: <CALCETrUW=r=xyr4pGiGnn9zUEevf=z6PP3111Ds6qguV5SjYUQ@mail.gmail.com>
From:   Matthew Garrett <mjg59@google.com>
Date:   Wed, 27 Mar 2019 10:42:18 -0700
Message-ID: <CACdnJus=zXgmNas+XVkWfe+ohAHEGMYLtfuYe0TH-eE=4p0oRw@mail.gmail.com>
Subject: Re: [PATCH V31 25/25] debugfs: Disable open() when kernel is locked down
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Greg KH <gregkh@linuxfoundation.org>,
        James Morris <jmorris@namei.org>,
        LSM List <linux-security-module@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        David Howells <dhowells@redhat.com>,
        Linux API <linux-api@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Wed, Mar 27, 2019 at 10:40 AM Andy Lutomirski <luto@kernel.org> wrote:
> As far as I'm concerned, preventing root from crashing the system
> should not be a design goal of lockdown at all.  And I think that the
> "integrity" mode should be as non-annoying as possible, so I think we
> should allow reading from debugfs.

I have no horse in this game - I'm happy to bring back the previous
approach for integrity mode and block reads entirely in
confidentiality mode, but I'd rather not spend another release cycle
arguing about it.