Re: [PATCH] don't allow CAP_NET_ADMIN to load non-netdev kernel modules

On Fri, Feb 25, 2011 at 12:25 -0500, Valdis.Kletnieks@vt.edu wrote:

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.

The threat is not a malicious root, but non-root with CAP_NET_ADMIN.
It's hardly possible to load arbitrary module into the kernel having
CAP_NET_ADMIN without other capabilities.

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).

No, I don't want to add anything about LSMs at all.


Thanks,

-- 
Vasiliy Kulikov
http://www.openwall.com - bringing security into open computing environments