Re: non-executable stack (via PT_GNU_STACK) not being enforced

[Kees Cook <kees@debian.org>]

Hi,

On Sun, Oct 10, 2010 at 01:35:10PM -0400, Brchk05 wrote:
> nx is in /proc/cpuinfo as a flag, though it does not appear at all in my dmesg output.  From what I can tell from the Ubuntu link you supplied, I am assuming this means that my CPU supports nx but I do not have the right type of kernel, i.e., one that uses PAE addressing, to support enforcement (or is that part Ubuntu specific).  Does this sound plausible?

That is quite likely, yes. If you're running 64bit, you already have PAE
mode. If you're running 32bit, you'll need to check your kernel's CONFIG
options for PAE. The default for 32bit is _not_ PAE mode, so this is
probably what is happening.

-Kees

-- 
Kees Cook                                            @debian.org