The logs in /var/log/cups are group owned by the group lp (or lpadmin). However cups runs as root:root. This is why it needs the dac_override capability to be able to access the log files (beside being allowed to access the log files).
The logs in /var/log/cups are group owned by the group lp (or lpadmin). However cups runs as root:root. This is why it needs the dac_override capability to be able to access the log files (beside being allowed to access the log files).