From: Valdis.Kletnieks@vt.edu
To: Vasiliy Kulikov <segoon@openwall.com>
Cc: "David S. Miller" <davem@davemloft.net>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
"Pekka Savola (ipv6)" <pekkas@netcore.fi>,
James Morris <jmorris@namei.org>,
Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
Patrick McHardy <kaber@trash.net>,
Eric Dumazet <eric.dumazet@gmail.com>,
Tom Herbert <therbert@google.com>,
Changli Gao <xiaosuo@gmail.com>, Jesse Gross <jesse@nicira.com>
Subject: Re: [PATCH] don't allow CAP_NET_ADMIN to load non-netdev kernel modules
Date: Fri, 25 Feb 2011 12:25:40 -0500 [thread overview]
Message-ID: <135187.1298654740@localhost> (raw)
In-Reply-To: Your message of "Fri, 25 Feb 2011 18:14:14 +0300." <20110225151414.GA5211@albatros>
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On Fri, 25 Feb 2011 18:14:14 +0300, Vasiliy Kulikov said:
> Since a8f80e8ff94ecba629542d9b4b5f5a8ee3eb565c any process with
> CAP_NET_ADMIN may load any module from /lib/modules/. This doesn't mean
> that CAP_NET_ADMIN is a superset of CAP_SYS_MODULE as modules are limited
> to /lib/modules/**. However, CAP_NET_ADMIN capability shouldn't allow
> anybody load any module not related to networking.
>
> This patch restricts an ability of autoloading modules to netdev modules
> with explicit aliases. Currently there are only three users of the
> feature: ipip, ip_gre and sit.
And you stop an attacker from simply recompiling the module with a suitable
MODULE_ALIAS line added, how, exactly? This patch may make sense down the
road, but not while it's still trivial for a malicious root user to drop stuff
into /lib/modules.
And if you're going the route "but SELinux/SMACK/Tomoyo will prevent a malicious
root user from doing that", then the obvious reply is "this should be part of those
subsystems rather than something done one-off like this (especially as it has a chance
of breaking legitimate setups that use the current scheme).
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next prev parent reply other threads:[~2011-02-25 17:28 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-24 15:12 module loading with CAP_NET_ADMIN Vasiliy Kulikov
2011-02-24 16:34 ` Ben Hutchings
2011-02-25 12:30 ` Vasiliy Kulikov
2011-02-25 15:14 ` [PATCH] don't allow CAP_NET_ADMIN to load non-netdev kernel modules Vasiliy Kulikov
2011-02-25 17:25 ` Valdis.Kletnieks [this message]
2011-02-25 17:47 ` Vasiliy Kulikov
2011-02-25 17:48 ` Ben Hutchings
2011-02-25 18:47 ` David Miller
2011-02-25 19:02 ` Vasiliy Kulikov
2011-02-25 19:05 ` David Miller
2011-02-25 19:07 ` Ben Hutchings
2011-02-25 19:16 ` David Miller
2011-02-25 19:30 ` Ben Hutchings
2011-02-25 19:43 ` David Miller
2011-02-25 19:53 ` Ben Hutchings
2011-02-25 20:37 ` David Miller
2011-02-25 20:38 ` Ben Hutchings
2011-02-25 20:59 ` Michał Mirosław
2011-02-27 20:22 ` Arnd Bergmann
2011-02-28 9:29 ` Michael Tokarev
2011-02-28 9:51 ` Vasiliy Kulikov
2011-02-28 19:23 ` David Miller
2011-03-01 19:48 ` [PATCH] net: " Vasiliy Kulikov
2011-03-01 20:13 ` Ben Hutchings
2011-03-01 21:33 ` [PATCH v2] " Vasiliy Kulikov
2011-03-02 7:15 ` Michael Tokarev
2011-03-09 22:06 ` Vasiliy Kulikov
2011-03-09 22:09 ` David Miller
2011-03-09 22:53 ` James Morris
2011-03-10 9:49 ` Vasiliy Kulikov
2011-03-02 16:01 ` Kees Cook
2011-03-02 19:39 ` Jake Edge
2011-03-02 19:43 ` Vasiliy Kulikov
2011-03-02 19:49 ` Jake Edge
2011-03-02 20:18 ` Vasiliy Kulikov
2011-03-02 20:38 ` Jake Edge
2011-03-02 20:40 ` Jake Edge
2011-03-22 20:47 ` Eric Paris
2011-03-22 20:47 ` Eric Paris
2011-03-24 15:37 ` Serge E. Hallyn
2011-03-24 18:03 ` Eric Paris
2011-03-24 18:33 ` Ben Hutchings
2011-03-24 20:26 ` Serge E. Hallyn
2011-03-24 21:39 ` Stephen Hemminger
2011-03-24 21:46 ` David Miller
2011-03-24 21:57 ` Serge E. Hallyn
2011-03-24 22:15 ` Eric Paris
2011-03-24 21:57 ` Greg KH
2011-03-26 10:35 ` Vasiliy Kulikov
2011-02-27 11:44 ` [PATCH] " Vasiliy Kulikov
2011-02-27 23:18 ` David Miller
2011-02-27 23:19 ` David Miller
2011-02-25 15:29 ` module loading with CAP_NET_ADMIN Michael Tokarev
2011-02-25 15:57 ` Vasiliy Kulikov
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