/usr/share/doc/libredcloth-ruby1.9.1/changelog.Debian.gz is in libredcloth-ruby1.9.1 4.2.8-2ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libredcloth-ruby1.9.1/../ruby-redcloth/changelog.Debian.gz