roles.rbac.authorization.k8s.io is forbidden even added in apiGroups

Question

I'm running kubernetes v1.11.5 and I'm installing helm with a tiller deployment for each namespace. Let's focus on a single namespace. This is the tiller service account configuration:

---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: tiller
  namespace: marketplace-int
---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: tiller-manager
  namespace: marketplace-int
rules:
- apiGroups:
  - ""
  - extensions
  - apps
  - rbac.authorization.k8s.io
  - roles.rbac.authorization.k8s.io
  - authorization.k8s.io
  resources: ["*"]
  verbs: ["*"]
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: tiller-binding
  namespace: marketplace-int
subjects:
- kind: ServiceAccount
  name: tiller
  namespace: marketplace-int
roleRef:
  kind: Role
  name: tiller-manager
  apiGroup: rbac.authorization.k8s.io

When I try to deploy a chart I get this error:

Error: release citest failed: roles.rbac.authorization.k8s.io "marketplace-int-role-ns-admin" is forbidden: 
attempt to grant extra privileges: 
[{[*] [*] [*] [] []}] user=&{system:serviceaccount:marketplace-int:tiller 5c6af739-1023-11e9-a245-0ab514dfdff4 
[system:serviceaccounts system:serviceaccounts:marketplace-int system:authenticated] map[]} 
ownerrules=[{[create] [authorization.k8s.io] [selfsubjectaccessreviews selfsubjectrulesreviews] [] []} 
{[get] [] [] [] [/api /api/* /apis /apis/* /healthz /openapi /openapi/* /swagger-2.0.0.pb-v1 /swagger.json /swaggerapi /swaggerapi/* /version /version/]} 
{[*] [ extensions apps rbac.authorization.k8s.io roles.rbac.authorization.k8s.io authorization.k8s.io] [*] [] []}] ruleResolutionErrors=[]

The error comes when trying to create rbac config for that namespace (with tiller sa):

# Source: marketplace/templates/role.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  labels:
    app: citest
    chart: marketplace-0.1.0
    heritage: Tiller
    release: citest
    namespace: marketplace-int
  name: marketplace-int-role-ns-admin
rules:
  - apiGroups: ["*"]
    resources: ["*"]
    verbs: ["*"]

The error message clearly says that the tiller service account doesn't have permission for roles.rbac.authorization.k8s.io but that permission is granted as showed previously.

$kubectl describe role tiller-manager
Name:         tiller-manager
Labels:       <none>
Annotations:  kubectl.kubernetes.io/last-applied-configuration:
                {"apiVersion":"rbac.authorization.k8s.io/v1","kind":"Role","metadata":{"annotations":{},"name":"tiller-manager","namespace":"marketplace-i...
PolicyRule:
  Resources                          Non-Resource URLs  Resource Names  Verbs
  ---------                          -----------------  --------------  -----
  *                                  []                 []              [*]
  *.apps                             []                 []              [*]
  *.authorization.k8s.io             []                 []              [*]
  *.extensions                       []                 []              [*]
  *.rbac.authorization.k8s.io        []                 []              [*]
  *.roles.rbac.authorization.k8s.io  []                 []              [*]

Honestly, I don't fully understand the error message to check if the ownerrules are fine and I'm trying to find out what does it means this kind of messages that seems to be related with the role description: {[*] [*] [*] [] []}

Any clue about what permissions I am missing?

Answer 1

This is due to permission escalation prevention in RBAC. See https://kubernetes.io/docs/reference/access-authn-authz/rbac/#privilege-escalation-prevention-and-bootstrapping for details.

Permission to create a role object is necessary, but not sufficient.

A user can only create/update a role if at least one of the following things is true:

1. they already have all the permissions contained in the role, at the same scope as the object being modified (cluster-wide for a ClusterRole, within the same namespace or cluster-wide for a Role). In your case, that would mean the user attempting to create the role must already have apiGroups=*, resources=*, verbs=* permissions within the namespace where it is attempting to create the role. You can grant this by granting the cluster-admin clusterrole to the serviceaccount within that namespace with a rolebinding.

2. they are given explicit permission to perform the "escalate" verb on the roles or clusterroles resource in the rbac.authorization.k8s.io API group (Kubernetes 1.12 and newer)