/usr/lib/ruby/vendor_ruby/ffi-glib/ is in ruby-gir-ffi 0.9.0-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/ffi-glib/array.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/array_methods.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/byte_array.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/bytes.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/container_class_methods.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/destroy_notify.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/error.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/hash_table.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/iconv.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/list.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/list_methods.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/main_loop.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/ptr_array.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/s_list.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/strv.rb
/usr/lib/ruby/vendor_ruby/ffi-glib/variant.rb