Comments on: Old news – Linux local root vulnerability

By: Matt Simmons

Matt Simmons — Wed, 19 Aug 2009 15:07:08 +0000

@Mike

Good link, thanks!

By: mike

mike — Wed, 19 Aug 2009 15:00:22 +0000

mmap_min_addr can be simple to bypass in many circumstances. Brad Spengler’s full disclosure of this is here: http://www.gossamer-threads.com/lists/fulldisc/full-disclosure/69537

By: anonymouscoward

anonymouscoward — Tue, 18 Aug 2009 17:31:49 +0000

Nope, not activated at all in kernel.

By: Matt Simmons

Matt Simmons — Tue, 18 Aug 2009 15:29:45 +0000

Weird. I don’t know, then. From everything I’ve read, you should be able to create it by echoing a number to the file.

Do you have SELinux enabled? I’ve also read that it prevents the altering of that setting, which may have the side-effect of removing the file from proc.

~$ /usr/sbin/sestatus
SELinux status: disabled

on mine, anyway.

By: anonymouscoward

anonymouscoward — Tue, 18 Aug 2009 15:21:21 +0000

Actually it does
# cat /proc/sys/vm/swappiness
60

2.6.28 x86_64

By: Matt Simmons

Matt Simmons — Tue, 18 Aug 2009 14:31:59 +0000

Hrm….then your kernel doesn’t support procfs?

You should upgrade when the patch comes out!

By: anonymouscoward

anonymouscoward — Tue, 18 Aug 2009 14:21:45 +0000

..and if it says
cat: /proc/sys/vm/mmap_min_addr: No such file or directory
?:)