Re: non-executable stack question

rbtqwt@xxxxxxxxx writes:

Is there a way to make non-executable the stack (or the heap) of a
process without patching the kernel?

On which platform?

On the original x86, there is no separate eXecute bit, so if the
memory is readable, it is also executable. You can make your stack
non-executable by mprotect(2)ing it with no PROT_READ, but your
program will not execute very far past that call :(

OTOH, on x86_64 (and recent Intel x86 processors), a separate
eXecute bit has been introduced, and on these processors you can
make your stack non-executable (with the same mprotect()) if the
kernel hasn't done that already.

Cheers,
--
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