Re: Worth using personality(ADDR_NO_RANDOMIZE) for EXEC_BACKEND on linux?

On 11/23/21, 11:29 AM, "Thomas Munro" <thomas.munro@gmail.com> wrote:
> Here's a patch for Linux and also FreeBSD.  The latter OS decided to
> turn on ASLR by default recently, causing my workstation to fail like
> this quite reliably, which reminded me to follow up with this.  It
> disables ASLR in pg_ctl and pg_regress, which is enough for check and
> check-world, but doesn't help you if you run the server directly
> (unlike the different hack done for macOS).
>
> For whatever random reason the failures are rarer on Linux (could be
> my imagination, but I think they might be clustered, I didn't look
> into the recipe for the randomness), but even without reproducing a
> failure it's clear to see using pmap that this has the right effect.
> I didn't bother with a check for the existence of ADDR_NO_RANDOMIZE
> because it's since 2.6.12 which is definitely ancient enough.

FWIW I just found this patch very useful for testing some EXEC_BACKEND
stuff on Linux.

Nathan