Bug#196575: xserver-xfree86 upgrade breaks X authorization

[Marius Gedminas <mgedmin@delfi.lt>]

On Sun, Jun 08, 2003 at 09:54:14AM -0500, Branden Robinson wrote:
> >   Xlib: connection to ":0.0" refused by server
> >   Xlib: Invalid XDM-AUTHORIZATION-1 key (failed key comparison)
> [...]
> > Plain startx used to work before I tried xdm/gdm, but now doesn't.
> 
> This data point is not consistent with any other reports.  Are you
> *sure* startx doesn't work?

Quite sure, I can reproduce it:

1) start xdm
2) log in
3) get the login screen back

At this point ~/.xsession-errors contains just three lines of text with
the same "connection refused by server" error message, coming from xrdb
this time.  (xrdb -merge ~/.Xresources is called early in my ~/.xsession
script, although it is not the first X client started -- xsetroot is the
first one, but strangely it does not complain.)

4) kill xdm
5) startx

I get the default X background pattern with an X-shaped mouse cursor,
and the following messages on the console:

[...]
Module Loader present
Markers: (--) probed, (**) from config file, (==) default setting,
(++) from command line, (!!) notice, (II) informational,
(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/XFree86.0.log", Time: Sun Jun  8 18:09:05 2003
(==) Using config file: "/etc/X11/XF86Config-4"
Skipping "/usr/X11R6/lib/modules/extensions/libGLcore.a:debug_xform.o":  No symbols found
Could not init font path element /usr/lib/X11/fonts/Speedo, removing from list!
AUDIT: Sun Jun  8 18:09:07 2003: 1220 X: client 1 rejected from local host
Auth name: XDM-AUTHORIZATION-1 ID: -1
Xlib: connection to ":0.0" refused by server
Xlib: Invalid XDM-AUTHORIZATION-1 key (failed key comparison)
waiting for X server to begin accepting connections .
AUDIT: Sun Jun  8 18:09:09 2003: 1220 X: client 1 rejected from local host
Auth name: XDM-AUTHORIZATION-1 ID: -1
Xlib: connection to ":0.0" refused by server
Xlib: Invalid XDM-AUTHORIZATION-1 key (failed key comparison)
..
AUDIT: Sun Jun  8 18:09:11 2003: 1220 X: client 1 rejected from local host
Auth name: XDM-AUTHORIZATION-1 ID: -1
Xlib: connection to ":0.0" refused by server
Xlib: Invalid XDM-AUTHORIZATION-1 key (failed key comparison)
.
giving up.
xinit:  unable to connect to X server
xinit:  No such process (errno 3):  Server error.

I killed the X server with Ctrl+Alt+Backspace after several seconds, I
guess, that's when xinit said "giving up".


It looks like that startx starts working again once I login successfully
with gdm2.  I guess the contents of my ~/.Xauthority have something to
do with it.

I've performing some tests with ~/.Xauthority removed:
1) startx creates two MIT-MAGIC-COOKIEs and works just fine, when
   .Xauthority is empty before running startx
2) kdm fails to show its login greeter and leaves an empty .Xauthority
   (obviously, since I never had the opportunity to log in)
3) gdm2 creates lots of MIT-MAGIC-COOKIEs and works just fine
4) xdm shows the login dialog but my .Xsession aborts with
      Xlib: connection to ":0.0" refused by server
      Xlib: Invalid XDM-AUTHORIZATION-1 key (failed key comparison)
      xrdb: Can't open display ':0'
5) xdm leaves ~/.Xauthority full of MIT-MAGIC-COOKIEs and
   XDM-AUTHORIZATION keys.  When these are present in .Xauthority file,
   startx stops working.

So it looks like the presence of XDM-AUTHORIZATION-1 keys breaks the
authorization.

I've saved copies of .Xauthority after each step.  Are you interested in
the output of 'xauth list' on each of those?

HTH,
Marius Gedminas
-- 
Westheimer's Discovery:
        A couple of months in the laboratory can
        frequently save a couple of hours in the library.