Switching users causes system crash

[GB]

Ubuntu 21.10

gdm3:
  Installed: 41~rc-0ubuntu2
  Candidate: 41~rc-0ubuntu2
  Version table:
 *** 41~rc-0ubuntu2 500
        500 http://us.archive.ubuntu.com/ubuntu impish/main amd64 Packages
        100 /var/lib/dpkg/status

Steps to reproduce:

1. Log in as any user
2. In the top right of the screen, click the power icon (⏻)
3. Select [Power Off/Log Out]
4. Select [Switch User]
5. Select any user that is NOT the user which is still currently logged in
6. Operating system is now frozen, mouse and keyboard don't respond, and user is never logged in.
7. Pressing [CTRL] + [ALT] + [DEL] appears to cause the system to crash

Apport.log: https://pastebin.com/srFwgfAh

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It sounds like some part of the system has crashed. To help us find the cause of the crash please follow these steps:

1. Look in /var/crash for crash files and if found run:
    ubuntu-bug YOURFILE.crash
Then tell us the ID of the newly-created bug.

2. If step 1 failed then look at https://errors.ubuntu.com/user/ID where ID is the content of file /var/lib/whoopsie/whoopsie-id on the machine. Do you find any links to recent problems on that page? If so then please send the links to us.

3. If step 2 also failed then apply the workaround from bug 994921, reboot, reproduce the crash, and retry step 1.

Please take care to avoid attaching .crash files to bugs as we are unable to process them as file attachments. It would also be a security risk for yourself.

[Daniel van Vugt (vanvugt)]

Actually nevermind that. I can tell from the hexadecimal addresses in the stack trace that this is bug 1945061.