Login Loop After Upgrade from 18.04 to 18.10

Question

Symptoms

Using GNOME desktop on 18.04 for a while now and everything has been working well. Upgraded to 18.10 yesterday and now stuck in a login loop.

I can solve the problem temporarily by CTRL + ALT + F3, logging in to the terminal and deleting my /home/user/.Xauthority file. Then returning to the greeter with ALT + -> and logging in works fine.

Once I reboot the machine the problem returns.

What Have I Tried

Looking at homedir permissions everything seems to be ok

$ls -lA | grep -E '.X|.ICE'
-rw-------  1 user user  1932 Oct 19 14:06 .ICEauthority
-rw-------  1 user user    52 Oct 19 14:06 .Xauthority

tmp permissions look ok

$ ls -ld /tmp
drwxrwxrwt 19 root root 12288 Oct 20 08:22 /tmp

Don't see anything bizarre in .xsession-errors

$ cat .xsession-errors
dbus-update-activation-environment: setting DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus
dbus-update-activation-environment: setting DISPLAY=:0
dbus-update-activation-environment: setting XAUTHORITY=/home/user/.Xauthority
dbus-update-activation-environment: setting GTK_MODULES=gail:atk-bridge
dbus-update-activation-environment: setting QT_ACCESSIBILITY=1
dbus-update-activation-environment: setting CLUTTER_IM_MODULE=xim
dbus-update-activation-environment: setting LANG=en_US.UTF-8
dbus-update-activation-environment: setting GDM_LANG=en_US
dbus-update-activation-environment: setting DISPLAY=:0
dbus-update-activation-environment: setting GTK2_MODULES=overlay-scrollbar
dbus-update-activation-environment: setting MANDATORY_PATH=/usr/share/gconf/ubuntu.mandatory.path
dbus-update-activation-environment: setting XDG_GREETER_DATA_DIR=/var/lib/lightdm-data/user
dbus-update-activation-environment: setting USER=user
dbus-update-activation-environment: setting DESKTOP_SESSION=ubuntu
dbus-update-activation-environment: setting QT4_IM_MODULE=xim
dbus-update-activation-environment: setting DEFAULTS_PATH=/usr/share/gconf/ubuntu.default.path
dbus-update-activation-environment: setting QT_QPA_PLATFORMTHEME=appmenu-qt5
dbus-update-activation-environment: setting PWD=/home/user
dbus-update-activation-environment: setting HOME=/home/user
dbus-update-activation-environment: setting QT_ACCESSIBILITY=1
dbus-update-activation-environment: setting XDG_SESSION_TYPE=x11
dbus-update-activation-environment: setting XDG_DATA_DIRS=/usr/share/ubuntu:/usr/local/share:/usr/share:/var/lib/snapd/desktop:/var/lib/snapd/desktop
dbus-update-activation-environment: setting XDG_SESSION_DESKTOP=ubuntu
dbus-update-activation-environment: setting GTK_MODULES=gail:atk-bridge
dbus-update-activation-environment: setting SHELL=/bin/bash
dbus-update-activation-environment: setting XDG_SEAT_PATH=/org/freedesktop/DisplayManager/Seat0
dbus-update-activation-environment: setting QT_IM_MODULE=ibus
dbus-update-activation-environment: setting XMODIFIERS=@im=ibus
dbus-update-activation-environment: setting IM_CONFIG_PHASE=2
dbus-update-activation-environment: setting XDG_CURRENT_DESKTOP=ubuntu:GNOME
dbus-update-activation-environment: setting GPG_AGENT_INFO=/run/user/1000/gnupg/S.gpg-agent:0:1
dbus-update-activation-environment: setting SHLVL=1
dbus-update-activation-environment: setting LANGUAGE=en_US
dbus-update-activation-environment: setting GDMSESSION=ubuntu
dbus-update-activation-environment: setting LOGNAME=user
dbus-update-activation-environment: setting DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus
dbus-update-activation-environment: setting XDG_RUNTIME_DIR=/run/user/1000
dbus-update-activation-environment: setting XAUTHORITY=/home/user/.Xauthority
dbus-update-activation-environment: setting XDG_SESSION_PATH=/org/freedesktop/DisplayManager/Session2
dbus-update-activation-environment: setting XDG_CONFIG_DIRS=/etc/xdg/xdg-ubuntu:/etc/xdg
dbus-update-activation-environment: setting PATH=/home/user/bin:/home/user/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
dbus-update-activation-environment: setting GTK_IM_MODULE=ibus
dbus-update-activation-environment: setting _=/usr/bin/dbus-update-activation-environment

LightDM reconfigure/remove/install

sudo dpkg-reconfigure lightdm
sudo apt-get purge lightdm
sudo apt-get install lightdm

Looked at lightdm logs and did not see anything there either.

From syslog I do notice this around the time I was logging in

Oct 19 14:01:27 computer systemd[1]: session-c1.scope: Killing process 2333 (lightdm) with signal SIGTERM.

Not sure what that is all about.

I am about out of ideas here so anyone have some more suggestions for what to try?

EDIT

Some more maybe helpful info. After reboot/login failure, followed by successful tty console login:

service lightdm status

● lightdm.service - Light Display Manager
   Loaded: loaded (/lib/systemd/system/lightdm.service; indirect; vendor preset: enabled)
  Drop-In: /lib/systemd/system/display-manager.service.d
           └─xdiagnose.conf
   Active: active (running) since Sat 2018-10-20 13:08:27 CDT; 1min 38s ago
     Docs: man:lightdm(1)
  Process: 1557 ExecStartPre=/bin/sh -c [ "$(basename $(cat /etc/X11/default-display-manager 2>/dev/null))" = "lightdm" ] (code=exited, status=0/SUCCESS)
 Main PID: 1563 (lightdm)
    Tasks: 26 (limit: 4915)
   Memory: 74.6M
   CGroup: /system.slice/lightdm.service
           ├─1563 /usr/sbin/lightdm
           ├─3530 /usr/lib/xorg/Xorg -core :0 -seat seat0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
           └─3748 lightdm --session-child 12 19

Oct 20 13:09:05 moltres lightdm[3560]: PAM unable to dlopen(pam_kwallet.so): /lib/security/pam_kwallet.so: cannot open shared object file: No such file or directory
Oct 20 13:09:05 moltres lightdm[3560]: PAM adding faulty module: pam_kwallet.so
Oct 20 13:09:05 moltres lightdm[3560]: PAM unable to dlopen(pam_kwallet5.so): /lib/security/pam_kwallet5.so: cannot open shared object file: No such file or directory
Oct 20 13:09:05 moltres lightdm[3560]: PAM adding faulty module: pam_kwallet5.so
Oct 20 13:09:05 moltres lightdm[3560]: pam_unix(lightdm-greeter:session): session opened for user lightdm by (uid=0)
Oct 20 13:09:06 moltres lightdm[3748]: PAM unable to dlopen(pam_kwallet.so): /lib/security/pam_kwallet.so: cannot open shared object file: No such file or directory
Oct 20 13:09:06 moltres lightdm[3748]: PAM adding faulty module: pam_kwallet.so
Oct 20 13:09:06 moltres lightdm[3748]: PAM unable to dlopen(pam_kwallet5.so): /lib/security/pam_kwallet5.so: cannot open shared object file: No such file or directory
Oct 20 13:09:06 moltres lightdm[3748]: PAM adding faulty module: pam_kwallet5.so
Oct 20 13:09:06 moltres lightdm[3748]: pam_succeed_if(lightdm:auth): requirement "user ingroup nopasswdlogin" not met by user "user"

Answer 1

I've had the same issue when updating from 18.04 to 18.10 and been searching for a solution for the past week. I haven't found one. There seems to be a lot of Arch users with the same problem.

The best work around is just typing in your password at the black/blank screen and the session unlocks.

I logged an ubuntu issue: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1802225

Answer 2

I had a similar problem. I'm running a Lenovo T430 with nvidia graphics, a quad core i7, 16GB ram, a 480GB solid state drive and a supported Sierra Wireless LTE WWAN card. I had previously installed fingerprint scanner support under 18.04 and have the system running (and booting) from a ZFS formatted drive. (I highly nonstandard configuration).Here's what I did to get it working.

I tried what you did to no avail. Mine hangs when I try to go into the desktop after logging in via tty3.

Reinstalling lightdm shouldn't help at all because Ubuntu 18.10 (and I believe 18.04) uses gdm3 as the default desktop manager. I tried reinstalling gdm3 using

sudo apt-get purge gdm3 sudo apt-get install gdm3

This brought up a purple screen saying I had two desktop managers installed and asking me to choose which to use. The two options were 'GDM3' and 'gdm3' , one in caps , one in lower case. I chose GDM3. It didn't work. So I uninstalled and reinstalled and selected gdm3. It still didn't work.

Next I uninstalled the fingerprint reader packages.

First install the gnome policykit. The fingerprint packages uninstall it so you need to put it back before you remove the fingerprint stuff or your login gets screwed up. (Well it is anyway, but I followed the procedure) sudo apt-get install policykit-1-gnome Then remove the fingerprint stuff. sudo apt-get purge libbsapi policykit-1-fingerprint-gui fingerprint-gui And it didn't work.

So I removed the gdm3 stuff again and made sure all the prices were gone, then reinstalled it. And it didn't work.

The following however DID work.

sudo apt-get purge gdm3 sudo apt-get install --reinstall gdm3 sudo apt-get install gnome

I'm not sure which of these fixed the problem, because I did both, rebooted and it logged in. Id try them one at a time and see if it works for you. (And report back if it does and leave the details either way) for anyone else that's having trouble.