gdm login screen says "Something went wrong please try again" three times and sends me back to the login screen when I'm not typing anything

[Jonathan Kamens]

After today's update to all of the current Hirsute packages, I can't login in. When I click on my username on the gdm3 login screen, it immediately displays with shaking the error "Sorry, that didn't work. Please try again." It does this three times, and then sends me back to the main login screen. It does this EVEN THOUGH I'M NOT TYPING ANYTHING. Please see the attached video.

I tried downgrading a bunch of packages but wasn't able to find a downgrade that made the problem go away.

ProblemType: Bug
DistroRelease: Ubuntu 21.04
Package: gdm3 3.38.1-2ubuntu1.1
ProcVersionSignature: Ubuntu 5.10.0-14.15-generic 5.10.11
Uname: Linux 5.10.0-14-generic x86_64
ApportVersion: 2.20.11-0ubuntu59
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: GNOME
Date: Sat Feb 27 16:20:47 2021
InstallationDate: Installed on 2019-08-16 (561 days ago)
InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416)
SourcePackage: gdm3
UpgradeStatus: Upgraded to hirsute on 2021-02-20 (6 days ago)

[Jonathan Kamens (jik)]

I figured out the problem. When I upgraded packages today, it uninstalled fprintd-clients but did not install libpam-fprintd. /etc/pam.d/gdm-fingerprint says that gdm is supposed to open pam_fprintd.so, but it couldn't because it wasn't available any longer.

I have no understanding of the intricacies of all the package dependencies that caused this broken situation to be allowed to occur. I will, however, mention that previous to today's package upgrade, I had open-fprintd installed, _not_ fprintd, because the fprintd that ships with Ubuntu is incompatible with my fingerprint reader (Lenovo Thinkpad X1 Carbon 6th gen). I don't know whether this is relevant to the problem that occurred here.

To fix this, I had to uninstall open-fprintd (which means I can no longer use my fingerprint reader) and install libpam-fprintd, which pulled in the fprintd package along with it even though that's useless to me since that fprintd doesn't work with my reader.

I am now unable to use open-fprintd because it conflicts with the fprintd package but I can't uninstall fprintd because that will cause libpam-fprintd to be uninstalled as well. But I'm going to open a separate ticket about that, since that's a different issue from the fact that today's upgrade made my system unusable as described above.

[Chris Guiver (guiverc)]

Possibly related to https://bugs.launchpad.net/ubuntu/+source/fprintd/+bug/1917178

[Daniel van Vugt (vanvugt)]

If you would like to keep this bug separate then please follow these instructions to check for crashes: https://wiki.ubuntu.com/Bugs/Responses#Missing_a_crash_report_or_having_a_.crash_attachment

Otherwise we can just group this with bug 1917178.

[Jonathan Kamens (jik)]

I don't understand why you are asking me for a crash report. You don't need a crash report to know what is going on here. I described to you exactly what is going on and exactly how to reproduce the issue: gdm fails in the way I described if libpam-fprintd isn't installed, and the web of dependencies of packages in Hirsute allowed an upgrade to uninstall fprintd-clients but did not require libpam-fprintd to be installed in its place.

It appears that perhaps a dependency to libpam-fprintd was added to the gdm3 package after I filed this issue, because I see that it has such a dependency now, and I don't see how I could have done the update before with that dependency in place without libpam-fprintd being installed during the update.

[Daniel van Vugt (vanvugt)]

Sorry, I was imagining a different error screen and couldn't see that error message in the attached video. It's a bit blurry but I will assume that's it...

Since there doesn't seem to be any crash there's no longer any reason to keep this separate from bug 1917178.

[Alex Sudakov (cygakob)]

I had a very similar problem:
whenever I clicked on a user at a login screen I had to type my password really quick in order for it not to be reset. Then sometimes login process stuck and I had to go into a text-based login prompt (ctrl+alt+f2) and then back to UI (ctrl+alt+f1) and this worked. Staying on the UI prompt didn't work.
After reading this thread I removed:
sudo apt purge --auto-remove fprintd libfprint-2-2

and I saw that option for fingerprint login disappeared from the user's settings menu.
I restarted my notebook and login screen worked without any issues.

I'm having HP EliteBook G8 and official Ubuntu notes at https://ubuntu.com/certified/202103-28761
 say:
"Fingerprint reader and WWAN hardware are not supported on this device"

However, I experimented with it trying to check it after fresh installation.

I hope these workarounds can help people struggling with the login as I did.
Also, if somebody wants any reports from me, I can try to install fprint libraries and reproduce it. Just let me know.