Greeter auth doesn't unlock unity lockscreen

The issue starts with that lightdm update, https://launchpad.net/ubuntu/+source/lightdm/1.16.1-0ubuntu1

The update changes the pam configuration, unsure if that could confuse unity in some way?

I believe this is due to the pam config changes rather than the code changes to lightdm. I commented out the new lines in the pam config files, rebooted, and then verified that the greeter auth works as intended.

I'm having trouble reproducing this as my graphics drivers just show a black screen when X quits.

I cannot reproduce this bug in Wily after latest updates.
Please update your system and make sure this still exist.

$ apt-cache policy lightdm
lightdm:
  Installed: 1.16.2-0ubuntu1
  Candidate: 1.16.2-0ubuntu1

neither lightdm nor unity changed

Tried this again I can reproduce it *only if* I switch to another user(name).

If the system has two (or more) users and I click another username from the indicator but instead I select my current logged-in user and write the password the lock screen blinks and asks for the password a second time. The second time accepts the password and unlocks the session.

If I click the 'Lock/Switch Account' in the indicator, greeter works as it should without problems.

This has been tested with package, https://launchpad.net/ubuntu/+source/lightdm/1.16.2-0ubuntu1

Any other test-case is welcome.

Regards
NickTh

tyhicks / others - does the libaudit functionality work if we revert the PAM configuration? i.e. is it a way forward to revert this PAM change until we work out what the problem is?

I've managed to reproduce on a VM, however commenting out the PAM changes seems to have no effect - it still shows the Unity lockscreen when returning from the greeter.

Robert, you have to reboot the system after reverting the PAM config changes.

Unfortunately, the PAM changes are required for the auditing functionality.

I am ok with reverting the entirety of the libaudit functionality in Wily until I can sort out this bug.

I've uploaded a version to wily with libaudit support disabled.

Also - confirming after reboot the changes worked.

This bug was fixed in the package lightdm - 1.16.3-0ubuntu1

---------------
lightdm (1.16.3-0ubuntu1) wily; urgency=medium

  * New upstream release:
    - Fix compile failing without libinput
    - Fix compile failing without Vala
  * debian/lightdm.lightdm-autologin.pam:
  * debian/lightdm.pam:
  * debian/rules:
    - Disable libaudit support for now - Unity is not unlocking with these
      changes (LP: #1498775)

 -- Robert Ancell <email address hidden> Wed, 30 Sep 2015 09:30:57 +1300