/usr/share/man/man8/auplink.8.gz is in aufs-tools 1:3.2+20130722-1.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man8/../man5/aufs.5.gz
/usr/share/man/man8/../man5/aufs.5.gz