/tmp directory does not have permissions to allow desktop to load

I recently installed Ubuntu 14.04.4 using LVM. /tmp was on its own logical volume.

I am using this computer as as LTSP server using ltsp-pnp. When the client image is built it used the permissions of /tmp prior to being mounted drwxr-xr-x (755). /tmp should have a permission of drwxrwxrwt (1777) even if it gets mounted over.

This wrong permission allowed the LTSP clients to boot but after a successful login, the client would never see the desktop but were sent back to the login screen. Changing the permissions of the client /tmp to 1777 allowed the client to login and work on the desktop.

I trying to fix this I tried a --bind mount to change the permissions of the /tmp directory. This worked to change the permissions of /tmp prior to mounting but did not change the /tmp in a newly built client image. I tried a second time booting with the Live CD. The permissions on the / (root) file system LV were correct.

I also tried booting in rescue mode and changing the permissions of the /tmp device before it was mounted to 1777 but after running ltsp-update-image once again this too failed to produce a client image with a properly permissioned /tmp.

I am reporting this here because alkisg at 03:09:58 PM in the ltsp irc channel asked me to. http://irclogs.ltsp.org/?d=2016-03-15

frederickjh: file a bug report under ltsp, I think it's an additional problem at ltsp-update-image

I have also added a comment to a ubiquity issue #371236 https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/371236

Current work around is to add the following to the [Default] section of lts.conf

# Fix permission on /tmp on the clients currently we have bug
# and they get mounted 755 instead of 1777
INIT_COMMAND_TMP="chmod 1777 /tmp"