/usr/share/doc/ruby-goocanvas/changelog.Debian.gz is in ruby-goocanvas 1.0.3-1build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/ruby-goocanvas/../ruby-glib2/changelog.Debian.gz
/usr/share/doc/ruby-goocanvas/../ruby-glib2/changelog.Debian.gz