[PATCH] Fix offset2lib issue for x86*, ARM*, PowerPC and MIPS

[Andrew Morton]

On Thu, 26 Feb 2015 15:34:36 -0800 Kees Cook <keescook at chromium.org> wrote:

> >> That pointless repetition should be avoided.
> >
> > That's surprisingly hard!
> >
> > After renaming mips brk_rnd() to mmap_rnd() I had a shot.  I'm not very
> > confident in the result.  Does that __weak trick even work?
> 
> In theory, it shouldn't be needed since only randomize_et_dyn will
> call mmap_rnd, and only architectures that use randomize_et_dyn will
> call it ... and will define mmap_rnd.

But randomize_et_dyn() is compiled for all architectures.  Or it was,
until I did the CONFIG_ARCH_HAVE_ELF_ASLR thing.

It seems odd that we have this per-arch feature but no Kconfig switch
for it.