Comment 35 for bug 1012081

According to upstream https://github.com/karelzak/util-linux, the version schema is:

          <major>.<minor>[.<maint>[.<bugfix>]]

             major = fatal and deep changes
             minor = typical release with new features
             maint = maintenance releases; bug fixes only
             bugfix = unplanned releases for critical/security bugs

So, I think updating 2.20.1 in trusty to 2.24.2 is safe.