lkml.org 
[lkml]   [2010]   [Nov]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [Security] proactive defense: using read-only memory
    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


    \
     
     \ /
      Last update: 2010-11-17 11:03    [W:0.019 / U:33.328 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site