[Sssd-maintainers] [Bug 2372533] New: Use `systemctl kill` in logrotate postrotate script

https://bugzilla.redhat.com/show_bug.cgi?id=2372533

Bug ID: 2372533
           Summary: Use `systemctl kill` in logrotate postrotate script
           Product: Fedora
           Version: 42
                OS: Linux
            Status: NEW
         Component: sssd
          Severity: low
          Assignee: [e-mail]
          Reporter: [e-mail]
        QA Contact: [e-mail]
                CC: [e-mail], [e-mail],
                    [e-mail], [e-mail],
                    [e-mail], [e-mail],
                    [e-mail]
  Target Milestone: ---
    Classification: Fedora

`systemctl kill` leverages systemd's knowledge of the daemon's main PID,
eliminating the need to rely on PID files or external tools like `killall` or
`pkill`. This ensures precise signal sending to the intended process, reducing
the risk of errors in process identification. Additionally, using `systemctl
kill` logs the signal sending in the service's journal, providing a record of
actions taken. Requires selinux-policy-41.43 or higher (see
https://bugzilla.redhat.com/show_bug.cgi?id=2369644), available as an update
for F41, F42, and Rawhide.

https://bodhi.fedoraproject.org/updates/FEDORA-2025-eb98eb9e24 (F41 -- will go
to stable in a few days)
https://bodhi.fedoraproject.org/updates/FEDORA-2025-f9f097f491 (F42 -- stable)
https://bodhi.fedoraproject.org/updates/FEDORA-2025-3db4c0ec1c (Rawhide)

The logrotate configuration snippet:

# cat /etc/logrotate.d/sssd
/var/log/sssd/*.log {
    weekly
    missingok
    notifempty
    sharedscripts
    rotate 2
    compress
    delaycompress
    su sssd sssd
    postrotate
        /bin/kill -HUP `cat /run/sssd/sssd.pid 2>/dev/null` 2> /dev/null ||
true
        /bin/pkill -HUP sssd_kcm 2> /dev/null || true
    endscript
}

In the postrotate script, kill and pkill can be replaced by:

/usr/bin/systemctl kill --signal=HUP --kill-whom=main sssd.service
sssd-kcm.service 2>/dev/null || true

Because:

# systemctl show -P MainPID sssd.service
1225
# cat /run/sssd/sssd.pid
1225

# systemctl show -P MainPID sssd-kcm.service
1447
# pgrep sssd_kcm
1447

Reproducible: Always

Additional Information:
sssd-common-2.11.0-1.fc42.x86_64