From: "Theo de Raadt" <deraadt@openbsd.org>
Subject: Re: fstat sysctl crashes kernel
To: "Todd C. Miller" <millert@openbsd.org>
Cc: Alexander Bluhm <bluhm@openbsd.org>, Vitaliy Makkoveev <otto@bsdbox.dev>, tech@openbsd.org
Date: Thu, 08 Aug 2024 09:47:27 -0600

Todd C. Miller <millert@openbsd.org> wrote:

> On Thu, 08 Aug 2024 13:21:54 +0200, Alexander Bluhm wrote:
> 
> > Independent of that, can we commit the chunk below?  When searching
> > for a specific process, there is not need to traverse the list to
> > the end.  Also I check for arg >= 0 as this is cosistent with the
> > arg < -1 check before.  Then you don't have to think about what is
> > special about process 0.  There is no functional difference as
> > process 0 has PS_SYSTEM set and is skipped anyway.
> 
> Yes, this makes sense. OK millert@

No matter what we do, we don't get an atomic view.  Punting the problem
to userland sidesteps the difficult problem in the kernel.