    def test_inject_files_with_bad_path(self):
        self.assertRaises(exception.Invalid,
                          disk_api._inject_file_into_fs,
                          '/tmp', '/etc/../../../../etc/passwd',
                          'hax')
The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.