Check IP addresses read in from dns-server.conf are valid before adding them to the array.
Check IP addresses read in from dns-server.conf are valid before adding them to the array.

Fix for CVE-2020-12620

Signed-off-by: Adam Warner <b1c1d8736f20db3fb6c1c66bb1455ed43909f0d8@adamwarner.co.uk>

jacobsalmela/AdminLTE,jacobsalmela/AdminLTE,jacobsalmela/AdminLTE,jacobsalmela/AdminLTE