This bug was fixed in the package ifupdown - 0.7.47.2ubuntu4.5
--------------- ifupdown (0.7.47.2ubuntu4.5) trusty; urgency=medium
* We are not even reading the contents of the per-interface state files when running ifquery, so there is no need to lock them. Not locking will allow ifquery to be called recursively from ifup and ifdown. (LP: #1701023)
-- Dan Streetman <email address hidden> Fri, 27 Apr 2018 09:03:18 -0400
This bug was fixed in the package ifupdown - 0.7.47.2ubuntu4.5
---------------
ifupdown (0.7.47.2ubuntu4.5) trusty; urgency=medium
* We are not even reading the contents of the per-interface state files
when running ifquery, so there is no need to lock them. Not locking
will allow ifquery to be called recursively from ifup and ifdown.
(LP: #1701023)
-- Dan Streetman <email address hidden> Fri, 27 Apr 2018 09:03:18 -0400