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Date:   Thu, 7 May 2020 14:53:15 -0400
From:   Rafael Aquini <aquini@redhat.com>
To:     Luis Chamberlain <mcgrof@kernel.org>
Cc:     linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org,
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        keescook@chromium.org, akpm@linux-foundation.org, cai@lca.pw,
        rdunlap@infradead.org
Subject: Re: [PATCH v2] kernel: add panic_on_taint
Message-ID: <20200507185315.GH205881@optiplex-lnx>
References: <20200507180631.308441-1-aquini@redhat.com>
 <20200507185046.GY11244@42.do-not-panic.com>
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On Thu, May 07, 2020 at 06:50:46PM +0000, Luis Chamberlain wrote:
> On Thu, May 07, 2020 at 02:06:31PM -0400, Rafael Aquini wrote:
> > Another, perhaps less frequent, use for this option would be
> > as a mean for assuring a security policy (in paranoid mode)
> > case where no single taint is allowed for the running system.
> 
> If used for this purpose then we must add a new TAINT flag for
> proc_taint() was used, otherwise we can cheat to show a taint
> *did* happen, where in fact it never happened, some punk just
> echo'd a value into the kernel's /proc/sys/kernel/tainted.
>

To accomplish that, the punk would need to be root, though, in which 
case everything else is doomed, already.
 
> Forunately proc_taint() only allows to *increment* the taint, not
> reduce.
> 
>   Luis
>