sudo apt-get install --reinstall apparmor
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 0 not upgraded.
Need to get 0 B/445 kB of archives.
After this operation, 0 B of additional disk space will be used.
Preconfiguring packages ...
(Reading database ... 413444 files and directories currently installed.)
Preparing to unpack .../apparmor_2.10.95-0ubuntu2_amd64.deb ...
Unpacking apparmor (2.10.95-0ubuntu2) over (2.10.95-0ubuntu2) ...
Processing triggers for systemd (229-4ubuntu5) ...
Processing triggers for ureadahead (0.100.0-19) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up apparmor (2.10.95-0ubuntu2) ...
update-rc.d: warning: start and stop actions are no longer supported; falling back to defaults
Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox
Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd