recent security updates to 10.3-RELEASE broke xdm?

[Polytropon]

On Sun, 2 Oct 2016 14:08:41 +0100 (BST), Anton Shterenlikht wrote:
> From freebsd at edvax.de Sun Oct  2 13:48:31 2016
> >> My xdm doesn't want to login me anymore.
> >> As soon as I enter the passwd, xdm reboots
> >> and presents me with the login prompt again.
> >
> >Can you start X without using XDM (i. e., by "startx")?
> 
> Yes, startx works fine.

Good, so a general X problem is out of the way.



> I'd still prefer to get xdm working again.

I can understand this intention, it's very convenient. :-)



> Apparently startx doesn't allow xconsole access to /dev/consile.

That is correct. When xdm starts a user session, it executes the
GiveConsole script which grants the access to the console device,
and TakeConsole after the session terminates to restore the defaults
(root access only).



> Anyway, this is what I get:
> 
> ####> cat .xsession
> #!/bin/tcsh
> source ~/.tcshrc
> exec ~/.xinitrc
> ####> cat .xinitrc
> xautolock -locker slock &
> xconsole &
> exec mwm

Yes: This should let the session live as long as mwm lives.
You can now easily verify this with the "non-xdm approach"
by using "startx" - you should get your regular desktop, and
when you exit mwm, the session terminates, and X shuts down.

This is what you should definitely verify, to make sure the
"session flow" works as expected.



> ####> cat .xsession-errors
> Protocol not supported by server                                                
> Error: Can't open display: :0                                                   
> Protocol not supported by server                                                
> Couldn't connect to :0                                                          
> Protocol not supported by server                                                
> mwm: Could not open display.                                                    

At the time mwm is started, there is no X display available
or you don't have permission to access it (which I see no
reason for).



> In fact startx works fine even without
> ~/.xinitrc. In that case it opens some
> default windows and uses twm.

Correct. The startx / xinit program defaults to a configuration
buried deep inside /usr/local to perform this default action.
If a ~/.xinitrc is present for the current user, it will be
executed instead.



> /var/log/xdm.log is not much help:
> 
> xdm info (pid 917): Starting X server on :0                                     
> xdm info (pid 4040): sourcing /usr/local/lib/X11/xdm/Xsetup_0                   
> xdm info (pid 4040): sourcing /usr/local/lib/X11/xdm/GiveConsole                
> xdm info (pid 4057): executing session /usr/local/lib/X11/xdm/Xsession          
> xdm info (pid 4040): sourcing /usr/local/lib/X11/xdm/TakeConsole                
> XIO:  fatal IO error 35 (Resource temporarily unavailable) on X server ":0"     
>       after 169 requests (162 known processed) with 0 events remaining.

This error also looks familiar to me. Do you have any suspicious
entries in the /var/log/Xorg.0.log file?

Checking for the error message in the questions list archive just
brought up this entry:

https://lists.freebsd.org/pipermail/freebsd-questions/2011-March/228663.html

No solution there, just a reference to the X11 list...




-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...