/usr/lib/ruby/ is in ruby-cri 2.10.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/cri/
/usr/lib/ruby/vendor_ruby/cri/argument_array.rb
/usr/lib/ruby/vendor_ruby/cri/command.rb
/usr/lib/ruby/vendor_ruby/cri/command_dsl.rb
/usr/lib/ruby/vendor_ruby/cri/command_runner.rb
/usr/lib/ruby/vendor_ruby/cri/commands/
/usr/lib/ruby/vendor_ruby/cri/commands/basic_help.rb
/usr/lib/ruby/vendor_ruby/cri/commands/basic_root.rb
/usr/lib/ruby/vendor_ruby/cri/core_ext/
/usr/lib/ruby/vendor_ruby/cri/core_ext/string.rb
/usr/lib/ruby/vendor_ruby/cri/core_ext.rb
/usr/lib/ruby/vendor_ruby/cri/help_renderer.rb
/usr/lib/ruby/vendor_ruby/cri/option_parser.rb
/usr/lib/ruby/vendor_ruby/cri/platform.rb
/usr/lib/ruby/vendor_ruby/cri/string_formatter.rb
/usr/lib/ruby/vendor_ruby/cri/version.rb
/usr/lib/ruby/vendor_ruby/cri.rb