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Message-ID: <8ee0b8e80809060934y385c1fefhd614befccbf64869@mail.gmail.com>
Date: Sat, 6 Sep 2008 18:34:56 +0200
From: "Jeroen van Rijn" <jvrnix@gmail.com>
To: "Ingo Molnar" <mingo@elte.hu>
Subject: Re: [patch] Add basic sanity checks to the syscall execution patch
Cc: "Willy Tarreau" <w@1wt.eu>,
       "Benjamin Herrenschmidt" <benh@kernel.crashing.org>,
       pageexec@freemail.hu, "Andi Kleen" <andi@firstfloor.org>,
       "Arjan van de Ven" <arjan@infradead.org>, linux-kernel@vger.kernel.org,
       tglx@tglx.de, hpa@zytor.com
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> a reboot often raises attention. But yes, in terms of end user boxes,
> probably not. Anyway, my points were about transparent rootkits
> installed on a running system without anyone noticing - obviously if the
> attacker can modify the kernel image and the user does not mind a reboot
> it's game over.
>

Hi,

can't then, in this scenario, the VFS keep tabs on /boot/vmlinuz and
only allow modification when the process in question properly
authenticates itself. As long as we're talking signed modules, why not
lock certain files down as well?

e.g. hand the kernel a signed list of files to watch write access to,
and allow only after the process auths via a private key.

-- Jeroen.

n.b. I understand this would slow down things more, but if we're
talking about taking extreme measures...