[Bug 1880193] Re: autofs: Assertion 'set_remove(iterator->links, link) == link' failed at src/shared/userdb.c:314, function userdb_on_query_reply(). Aborting.

[Paride Legovini]

Hello Michael, thanks for the followup and for filing the bug in the
first place.

For the moment I'm changing the status of this report to Incomplete
across the packages/series it targets. If this specific issue can't be
reproduced anymore please set the statuses to Invalid (I'd prefer it to
Fix Released as we didn't identify what actually fixed it), and go ahead
filing a new bug for the remaining issues you're facing. On the other
hand if you still think this should be investigated please comment back
with your findings, change the bug status back to New and we'll look at
it again. Thanks!

** Changed in: autofs (Ubuntu)
       Status: Triaged => Incomplete

** Changed in: autofs (Ubuntu Focal)
       Status: Triaged => Incomplete

** Changed in: systemd (Ubuntu)
       Status: Triaged => Incomplete

** Changed in: systemd (Ubuntu Focal)
       Status: Triaged => Incomplete

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to autofs in Ubuntu.
https://bugs.launchpad.net/bugs/1880193

Title:
  autofs: Assertion 'set_remove(iterator->links, link) == link' failed
  at src/shared/userdb.c:314, function userdb_on_query_reply().
  Aborting.

Status in autofs package in Ubuntu:
  Incomplete
Status in systemd package in Ubuntu:
  Incomplete
Status in autofs source package in Focal:
  Incomplete
Status in systemd source package in Focal:
  Incomplete

Bug description:
  autofs has a periodic error on mounting shares in Ubuntu 20.04 (it happens about 1 time out of 5):
  "Assertion 'set_remove(iterator->links, link) == link' failed at src/shared/userdb.c:314, function userdb_on_query_reply(). Aborting.
  Aborted (core dumped)"


  `autofs.service` restart (or `automount` app restart) fixes this
  issue. However if some of home dirs (like `Desktop` or `Documents`)
  are mounted by `autofs`, user can't login into Ubuntu Desktop
  Environment (PC freezes on login with black screen). Since this error
  can prevent user log in, it might be considered as critical bug.


  It happens both in `autofs` systemd service and by direct execution of
  `automount` app (`automount -f -d` command).


  May be it's an underlying error in `systemd` library (I found the
  line, mentioned in error, in its source codes).


  This issue has place in Ubuntu 20.04 (it works correctly in Ubuntu
  18.04):

  > lsb_release -rd
  Description: Ubuntu 20.04 LTS
  Release: 20.04


  Packages versions:

  > apt-cache policy autofs systemd
  autofs:
    Installed: 5.1.6-2
    Candidate: 5.1.6-2
    Version table:
   *** 5.1.6-2 500
          500 http://ru.archive.ubuntu.com/ubuntu focal/main amd64 Packages
          100 /var/lib/dpkg/status
  systemd:
    Installed: 245.4-4ubuntu3
    Candidate: 245.4-4ubuntu3
    Version table:
   *** 245.4-4ubuntu3 500
          500 http://ru.archive.ubuntu.com/ubuntu focal/main amd64 Packages
          100 /var/lib/dpkg/status


  Steps to reproduce:
  1. Ubuntu 20.04 clean install
  2. `apt install realmd sssd sssd-tools libnss-sss libpam-sss adcli samba-common-bin`
  3. `realm join DOMAIN.NAME`
  4. Enable makehomedir by command: `pam-auth-update`
  5. `apt install cifs-utils`
  6. `apt install autofs`
  7. Add next line inside [domain/DOMAIN.EXT] section into /etc/sssd/sssd.conf: `krb5_ccname_template = FILE:%d/krb5cc_%U`
  8. Reboot
  9. Login as domain user and try to open directory, mounted by `autofs` (in my configuration shares are provided by AD).
  10. `autofs.service` stops with the error above about 1 time out of 5 (not always).

  Found workaround:
  Add `Restart=always` into `[Service]` section in `/lib/systemd/system/autofs.service` file (in other words configure auto-restart on failures for autofs service).


  Attachments:
  1. Full log of `automount -f -d` command.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/autofs/+bug/1880193/+subscriptions