Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Thu, 7 May 2020 22:25:58 +0000
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Rafael Aquini <aquini@redhat.com>
Cc:     Tso Ted <tytso@mit.edu>, Adrian Bunk <bunk@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Laura Abbott <labbott@redhat.com>,
        Jeff Mahoney <jeffm@suse.com>, Jiri Kosina <jikos@kernel.org>,
        Jessica Yu <jeyu@suse.de>, Takashi Iwai <tiwai@suse.de>,
        Ann Davis <AnDavis@suse.com>,
        Richard Palethorpe <rpalethorpe@suse.de>,
        linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org,
        dyoung@redhat.com, bhe@redhat.com, corbet@lwn.net,
        keescook@chromium.org, akpm@linux-foundation.org, cai@lca.pw,
        rdunlap@infradead.org
Subject: Re: [PATCH v2] kernel: add panic_on_taint
Message-ID: <20200507222558.GA11244@42.do-not-panic.com>
References: <20200507180631.308441-1-aquini@redhat.com>
 <20200507182257.GX11244@42.do-not-panic.com>
 <20200507184307.GF205881@optiplex-lnx>
 <20200507184705.GG205881@optiplex-lnx>
 <20200507203340.GZ11244@42.do-not-panic.com>
 <20200507220606.GK205881@optiplex-lnx>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20200507220606.GK205881@optiplex-lnx>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Thu, May 07, 2020 at 06:06:06PM -0400, Rafael Aquini wrote:
> On Thu, May 07, 2020 at 08:33:40PM +0000, Luis Chamberlain wrote:
> > I *think* that a cmdline route to enable this would likely remove the
> > need for the kernel config for this. But even with Vlastimil's work
> > merged, I think we'd want yet-another value to enable / disable this
> > feature. Do we need yet-another-taint flag to tell us that this feature
> > was enabled?
> >
> 
> I guess it makes sense to get rid of the sysctl interface for
> proc_on_taint, and only keep it as a cmdline option. 

That would be easier to support and k3eps this simple.

> But the real issue seems to be, regardless we go with a cmdline-only option
> or not, the ability of proc_taint() to set any arbitrary taint flag 
> other than just marking the kernel with TAINT_USER. 

I think we would have no other option but to add a new TAINT flag so
that we know that the taint flag was modified by a user. Perhaps just
re-using TAINT_USER when proc_taint() would suffice.

  Luis