ports/154502: x11/xdm authorization failure when used with E17 window manager

[Jilles Tjoelker]

The following reply was made to PR ports/154502; it has been noted by GNATS.

From: Jilles Tjoelker <jilles at stack.nl>
To: bug-followup at FreeBSD.org, cpt_complain at yahoo.com
Cc:  
Subject: Re: ports/154502: x11/xdm authorization failure when used with E17
 window manager
Date: Wed, 12 Jun 2013 22:46:57 +0200

 In FreeBSD PR 154502, you wrote:
 > Xdm authorization fails after user login.
 > The user is unable to start an E17 window manager session, and is
 > returned to the xdm login screen.
 
 > Fix: Need to add the missing option:
 > DisplayManager*authName: MIT-MAGIC-COOKIE-1
 
 I take it that the error message
   XDM authorization key matches an existing client!
 appears in .xsession-errors.
 
 I recently encountered this issue when trying to log in using xdm and
 xfce4-session. Adding the quoted line to xdm-config fixed the problem
 for me.
 
 The cause is that the implementation of XDM-AUTHORIZATION-1 is broken if
 applications execve or unload/reload libX11/libxcb between connections
 to the X server. More information can be found in
 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=486606
 
 Since it is unclear whether XDM-AUTHORIZATION-1 will be fixed and if so,
 where, I think it is best to disable it in xdm. It looks like adding
 --disable-xdm-auth to xdm's configure flags will do this but I have not
 tested it. I think the security impact is minimal; gdm does not use
 XDM-AUTHORIZATION-1 either.
 
 -- 
 Jilles Tjoelker