Issue

IP v4 address block 172.16.0.0/12 is a private, non-routable address range. Adding any address within that range should pass the overlap checks. However, attempting to add such causes a complaint about overlap then a command failure.

Steps to Reproduce

1. Using the gui, surf to dns zones.
2. Choose 'Reverse zone IP network'.
3. Attempt to add any subnet within 172.16.0.0/12 (or the whole thing). Do no click 'skip overlap check'.

Actual behavior

Notice the error message. Command failure.

Expected behavior

There should be no conflicts with arin addresses reported when creating reverse ip zones for any RFC1918 subnet.

Version/Release/Distribution

$ rpm -q freeipa-server freeipa-client ipa-server ipa-client 389-ds-base pki-ca krb5-server

freeipa-server-4.7.2-1.1.fc29.x86_64
freeipa-client-4.7.2-1.1.fc29.x86_64
package ipa-server is not installed
package ipa-client is not installed
389-ds-base-1.4.0.22-1.fc29.x86_64
pki-ca-10.6.9-1.fc29.noarch
krb5-server-1.16.1-25.fc29.x86_64

Additional info:

Any additional information, configuration, data or log snippets that is needed for reproduction or investigation of the issue.

Log file locations: https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Linux_Domain_Identity_Authentication_and_Policy_Guide/config-files-logs.html
Troubleshooting guide: https://www.freeipa.org/page/Troubleshooting