Kiosk mode fails when using generated xorg.conf

[Vinicius Massuchetto]

Ubuntu 11.04
LTSP Server version 5.2.8-0ubuntu1 i386

While setting KIOSK_EXE to some custom app on lts.conf I get a Xorg error that stops on the screen:

"Invalid argument for -config. For non-root users, the file specified with -config must be a relative path and must not contain any ".." elements. Using default xorg.conf search path."

Running `ps -ef` on the client I get the line:
xinit /usr/share/ltsp/xinitrc /usr/share/ltsp/kioskSession <custom_script> -- :7 vt7 -config /var/run/ltsp-xorg.conf -br

On file: /opt/ltsp/i386/usr/share/ltsp/screen.d/kiosk
In this line:
su - ${KIOSKUSER} -c "XINITRC_DAEMON=${XINITRC_DAEMON} xinit $xinitrc /usr/share/ltsp/kioskSession ${KIOSK_EXE} ${KIOSK_OPTIONS} -- ${DISPLAY} vt${TTY} ${X_ARGS} -br" >/dev/null

If I remove ${X_ARGS} things work fine. However, the X_BLANKING option seem not to work when doing this.

Please let me know about any other information that I can provide to troubleshoot this.

[Vagrant Cascadian (vagrantc)]

Since the kiosk screen script runs xinit as the user, any options in ltsp's screen-session.d that trigger generation and specifying a custom xorg.conf will fail, as only root can specify an alternate xorg.conf with a full path using the "-config" option to X. This may require some rethinking of xorg.conf generation...

[Juuso Alasuutari (juuso-alasuutari)]

Reporting a workaround for Ubuntu 14.04.1 LTS:

Editing the file /usr/share/ltsp/screen-session.d/XS00-setvars by changing the line

    XCONF=/var/run/ltsp-xorg.conf

to

    XCONF=var/run/ltsp-xorg.conf

allows kiosk mode to work. I don't know what this workaround does in all use cases, and I wouldn't be surprised if it ends up breaking something. Hopefully someone who knows more about the inner workings of LTSP can comment.

[Alkis Georgopoulos (alkisg)]

In the file /usr/share/ltsp/screen-session.d/XS90-set-x-conf
can you change this line:
    X_ARGS="$X_ARGS -config $X_CONF"
to:
    X_ARGS="$X_ARGS -config $(realpath --relative-to=. "$X_CONF")"
...and see if this works for all cases, i.e. both in kiosk and in normal setups?

[Alkis Georgopoulos (alkisg)]

In a normal setup it works for me, producing this command line:
/usr/lib/xorg/Xorg :7 vt7 -auth /var/run/ldm-xauth-dj3cvnFnW/Xauthority -listen tcp -config run/ltsp-xorg.conf -br

If it works for kiosk as well, I'll commit it.

[Vagrant Cascadian (vagrantc)]

I was able to reproduce this in older versions of Debian, but recent versions of X.org (found in stretch/testing) don't seem to have this problem... that said, KIOSK mode fails entirely for other reasons...

[Launchpad Janitor (janitor)]

[Expired for LTSP because there has been no activity for 60 days.]