Re: kern/51654: wrong ps_strings breaks emacs20

[Joerg Sonnenberger <joerg%bec.de@localhost>]

The following reply was made to PR kern/51654; it has been noted by GNATS.

From: Joerg Sonnenberger <joerg%bec.de@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
	netbsd-bugs%netbsd.org@localhost
Subject: Re: kern/51654: wrong ps_strings breaks emacs20
Date: Sat, 26 Nov 2016 06:49:24 +0100

 On Sat, Nov 26, 2016 at 04:00:00AM +0000, dholland%NetBSD.org@localhost wrote:
 > After updating emacs dumps core. After spending a long time barking up
 > the wrong PaX tree, it seems that the problem is that an invalid
 > pointer is being provided in __ps_strings and this causes _libc_init
 > to segv.
 
 The address space layout changed. ps_strings is placed at the very top,
 without PAX it is at a fixed address.
 
 > I haven't the slightest idea why this happens only with emacs but I
 > imagine it's a consequence of the emacs dump/undump mechanism somehow.
 
 Combine this with the changed MAXUSER address and now certain cached
 locations no longer match.
 
 Joerg