Currently oc adm policy add-scc-to-user modifies SCC directly but should rather create appropriate ClusterRole and ClusterRoleBinding instead and not modify SCC at all.
PRs in the queue.
Confirmed with latest oc , the issue has fixed:
[root@dhcp-140-138 ~]# oc version --client -o yaml
[root@dhcp-140-138 ~]# oc adm policy add-scc-to-user privileged testuser-1
clusterrole.rbac.authorization.k8s.io/system:openshift:scc:privileged added: "testuser-1"
[root@dhcp-140-138 ~]# oc get clusterrole |grep privileged
[root@dhcp-140-138 ~]# oc get clusterrolebinding |grep privileged
system:openshift:scc:privileged ClusterRole/system:openshift:scc:privileged 2m49s
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.