Bug#365134: confirmation of severe xdm bug

[Ian Bruce <ian_bruce@fastmail.fm>]

I'd like to confirm the seriousness of this bug. I have a pre-Xorg
X-server, but I thought I would try upgrading xdm to see if that would
fix some minor problems associated with "/etc/init.d/xdm restart".
Instead, it broke the X-server completely.

The original submitter is correct that xdm looks for some executables in
the wrong places:

# strings /usr/bin/xdm | grep usr
/usr/bin/xrdb
/usr/bin/xterm -ls
/usr/bin/xterm
/usr/lib/X11/xdm/chooser
:0 local /usr/bin/X :0
/bin:/usr/bin:/usr/bin:/usr/ucb
/etc:/bin:/usr/bin:/usr/bin:/usr/ucb
/usr/lib/X11/xdm/libXdmGreet.so

The file /etc/X11/xdm/Xservers has the same wrong location for the
X-server binary. I was able to fix this with a few symlinks, but if I
hadn't seen his report of what the problem was, I wouldn't have had a
clue.

# ls -l /usr/bin/X /usr/bin/xrdb 
lrwxrwxrwx 1 root root 5 2006-04-28 14:48 /usr/bin/X -> X11/X
lrwxrwxrwx 1 root root 8 2006-04-28 14:48 /usr/bin/xrdb -> X11/xrdb

In order to fix this reliably, why not give the PATH variable a
reasonable value, and then let execlp() find the actual location of the
executables? Either that, or have the xdm package create these same
symlinks.

As the original report says, it is also necessary to change the
references in /etc/init.d/xdm and /etc/X11/default-display-manager from
"/usr/bin/X11/xdm" to "/usr/bin/xdm". It's hard to see how this problem
arose, because these files all come from the same package; there's no
question of a version conflict.


-- Ian Bruce