[lkml]   [2017]   [Nov]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 00/23] KAISER: unmap most of the kernel from userspace page tables
On Wed 2017-11-22 17:19:07, Pavel Machek wrote:
> Hi!
> > KAISER makes it harder to defeat KASLR, but makes syscalls and
> > interrupts slower. These patches are based on work from a team at
> > Graz University of Technology posted here[1]. The major addition is
> > support for Intel PCIDs which builds on top of Andy Lutomorski's PCID
> > work merged for 4.14. PCIDs make KAISER's overhead very reasonable
> > for a wide variety of use cases.
> Is it useful?
> > Full Description:
> >
> > KAISER is a countermeasure against attacks on kernel address
> > information. There are at least three existing, published,
> > approaches using the shared user/kernel mapping and hardware features
> > to defeat KASLR. One approach referenced in the paper locates the
> > kernel by observing differences in page fault timing between
> > present-but-inaccessable kernel pages and non-present pages.
> I mean... evil userspace will still be able to determine kernel's
> location using cache aliasing effects, right?

Issues with AnC attacks are tracked via several CVE identifiers.

CVE-2017-5925 is assigned to track the developments for Intel processors
CVE-2017-5926 is assigned to track the developments for AMD processors


(cesky, pictures)
[unhandled content-type:application/pgp-signature]
 \ /
  Last update: 2017-11-23 11:48    [W:0.303 / U:0.328 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site