Após instalar o ubuntu 17.10, comecei a receber esse erro na inicialização. Aqui está a saída de
$ sudo service apparmor status
pparmor.service - AppArmor initialization
Loaded: loaded (/lib/systemd/system/apparmor.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Tue 2017-11-07 08:48:16 EET; 10min ago
Docs: man:apparmor(7)
http://wiki.apparmor.net/
Main PID: 621 (code=exited, status=123)
Nov 07 08:48:16 logician-724 apparmor[621]: Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd
Nov 07 08:48:16 logician-724 apparmor[621]: Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox
Nov 07 08:48:16 logician-724 apparmor[621]: AppArmor parser error for /etc/apparmor.d/usr.bin.webbrowser-app in /etc/apparmor.d/usr.bin.webbrowser-app at line 26: Could not open '/usr/share/
Nov 07 08:48:16 logician-724 apparmor[621]: AppArmor parser error for /etc/apparmor.d/usr.lib.mediascanner-2.0.mediascanner-extractor in /etc/apparmor.d/usr.lib.mediascanner-2.0.mediascanner
Nov 07 08:48:16 logician-724 apparmor[621]: Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd
Nov 07 08:48:16 logician-724 apparmor[621]: ...fail!
Nov 07 08:48:16 logician-724 systemd[1]: apparmor.service: Main process exited, code=exited, status=123/n/a
Nov 07 08:48:16 logician-724 systemd[1]: Failed to start AppArmor initialization.
Nov 07 08:48:16 logician-724 systemd[1]: apparmor.service: Unit entered failed state.
Nov 07 08:48:16 logician-724 systemd[1]: apparmor.service: Failed with result 'exit-code'.