The fix has cause to regression bug https://bugzilla.redhat.com/show_bug.cgi?id=1601378

Verify on v3.7.61, no error log "Error creating subnet for node"

[root@dma37-master-etcd-nfs-1 ~]# oc version
oc v3.7.61
kubernetes v1.7.6+a08f5eeb62
features: Basic-Auth GSSAPI Kerberos SPNEGO

Server https://dma37-master-etcd-nfs-1:8443
openshift v3.7.61
kubernetes v1.7.6+a08f5eeb62
[root@dma37-master-etcd-nfs-1 ~]# oc get node
NAME                           STATUS    AGE       VERSION
dma37-master-etcd-nfs-1        Ready     2h        v1.7.6+a08f5eeb62
dma37-node-registry-router-1   Ready     2h        v1.7.6+a08f5eeb62

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2018:2337