Re: How to mitigate affect of reducing PAX_ASLR_DELTA_STACK_LSB to 2

[Martin Husemann <martin%duskware.de@localhost>]

On Mon, Jun 26, 2017 at 07:31:30PM +0000, Christos Zoulas wrote:
> The other way to do this would be to randomly adjust the stack start after
> it has been allocated by the vm system...

Like in ld.elf_so, or for static binaries the csu code: just generate
a random number, apply alignement, and decrease/increase stack pointer
by the result. We could even supply the random value from the kernel
in the aux vector.

Note that alignment restrictions for the stack are machine dependend, double
word aligned is not always good enough.

Martin