Re: Patch 4/6 randomize the stack pointer

[Arjan van de Ven]

On Sat, 2005-01-29 at 11:21 -0500, John Richard Moser wrote:
> -----BEGIN PGP SIGNED MESSAGE-----

> These are the only places mprotect() is mentioned; a visual scan
> confirms no trickery:
> 
>         if( fork() == 0 ) {
>                 /* Perform a dirty (but not unrealistic) trick to circumvent
>                  * the kernel protection.
>                  */
>                 if( paxtest_mode == 1 ) {
>                         pthread_t thread;
>                         pthread_create(&thread, NULL, test_thread, dummy);
>                         doit();
>                         pthread_kill(thread, SIGTERM);
>                 } else {

> So, there you have it.  These tests do not intentionally kill
> exec-shield based on its known issue with tracking the upper limit of
> the code segment.


here they do.
dummy is a local NESTED function, which causes the stack to *correctly*
be marked executable, due to the need of trampolines. 
That disables execshield for any tests that use dummy.o, which most of
them are.

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