Messages in this thread | | | Date | Wed, 17 Nov 2010 11:00:54 +0100 | From | Pavel Machek <> | Subject | Re: [Security] proactive defense: using read-only memory |
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Hi!
> - Modules need to be correctly marked RO/NX. This patch exists[3], but is > not in mainline. It needs to be in mainline.
Why not.
> - Pointers to function table also need to be marked read-only after > they are set. An example of this is the security_ops table pointer. It > gets set once at boot, and never changes again. These need to be handled > so it isn't possible to just trivially reaim the entire security_ops > table lookup somewhere else.
But there are too many of those. You can't block them all...
> - Entry points to set_kernel_text_rw() and similar need to be blockable. > Having these symbols available make kernel memory modification trivial;
What prevents attacker to just inlining those functions in the exploit?
If you want protection domain inside kernel, perhaps you should take ukernel approach?
-- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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