Bugtraq: Re: non-exec stacks on solaris.

[casper () HOLLAND SUN COM (Casper Dik)]

> not long ago, someone posted that you can disable execution of
> instructions on the stack via /etc/system for solaris.  There
> appears to be three variables for this:
>
> noexec_user_stack
> noexec_user_stack_log
> noexec_zfod_argsp
>
> The first two are pretty obvious, but what about the third ?

The first two (new in 2.6) are, indeed, obvious.  (Note that they
exist in all kernels but only work on sun4m/sun4d and Ultras)

Noexec_zfod_argsp is the variable used by the mechanism internally;
it's the argument pointer used to initialize the page protection
by the stack.  It's not a variable you can set.

(i.e., the variable contains the protection bits as used on a
"noexec" zero-fill-on-demand page.

Casper