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Message-ID: <fbf37518-328d-c08c-7140-5d09d7a2674f@redhat.com>
Date:   Fri, 5 May 2023 09:35:59 +0200
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Subject: Re: [PATCH] sysctl: add config to make randomize_va_space RO
To:     Michael McCracken <michael.mccracken@gmail.com>,
        linux-kernel@vger.kernel.org
Cc:     kernel-hardening@lists.openwall.com, serge@hallyn.com,
        tycho@tycho.pizza, Luis Chamberlain <mcgrof@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Iurii Zaikin <yzaikin@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org
References: <20230504213002.56803-1-michael.mccracken@gmail.com>
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From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20230504213002.56803-1-michael.mccracken@gmail.com>
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On 04.05.23 23:30, Michael McCracken wrote:
> Add config RO_RANDMAP_SYSCTL to set the mode of the randomize_va_space
> sysctl to 0444 to disallow all runtime changes. This will prevent
> accidental changing of this value by a root service.
> 
> The config is disabled by default to avoid surprises.

Can you elaborate why we care about "accidental changing of this value 
by a root service"?

We cannot really stop root from doing a lot of stupid things (e.g., 
erase the root fs), so why do we particularly care here?

-- 
Thanks,

David / dhildenb