Am trying to better understand RBAC in kubernetes. Came across this unexpected situation where authorization test using kubectl auth can-i and actual results are different. In short, newly created user should not be able to get pods as per this test, however this user can actually get pods.

Version:

$ kubectl version
Client Version: version.Info{Major:"1", Minor:"11", GitVersion:"v1.11.1", GitCommit:"b1b29978270dc22fecc592ac55d903350454310a", GitTreeState:"clean", BuildDate:"2018-07-17T18:53:20Z", GoVersion:"go1.10.3", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"11", GitVersion:"v1.11.1", GitCommit:"b1b29978270dc22fecc592ac55d903350454310a", GitTreeState:"clean", BuildDate:"2018-07-17T18:43:26Z", GoVersion:"go1.10.3", Compiler:"gc", Platform:"linux/amd64"}

kubectl config for user in questions:

$ kubectl config view --minify
apiVersion: v1
clusters:
- cluster:
    certificate-authority: /home/master/ca.pem
    server: https://192.168.1.111:6443
  name: jdoe
contexts:
- context:
    cluster: jdoe
    user: jdoe
  name: jdoe
current-context: jdoe
kind: Config
preferences: {}
users:
- name: jdoe
  user:
    client-certificate: /home/master/jdoe.pem
    client-key: /home/master/jdoe-key.pem

The test against authorization layer says jdoe cannot get pods.

$ kubectl auth can-i get pods --as jdoe
no

However, jdoe can get pods:

$ kubectl get pods --all-namespaces
NAMESPACE       NAME                                       READY     STATUS    RESTARTS   AGE
ingress-nginx   nginx-ingress-controller-87554c57b-ttgwp   1/1       Running   0          5h
kube-system     coredns-5f7d467445-ngnvf                   1/1       Running   0          1h
kube-system     coredns-5f7d467445-wwf5s                   1/1       Running   0          5h
kube-system     weave-net-25kq2                            2/2       Running   0          5h
kube-system     weave-net-5njbh                            2/2       Running   0          4h

Got similar results from auth layer after switching back to admin context:

$ kubectl config use-context kubernetes
Switched to context "kubernetes".
$ kubectl config view --minify
apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: REDACTED
    server: https://192.168.1.111:6443
  name: kubernetes
contexts:
- context:
    cluster: kubernetes
    user: admin
  name: kubernetes
current-context: kubernetes
kind: Config
preferences: {}
users:
- name: admin
  user:
    client-certificate: /home/master/admin.pem
    client-key: /home/master/admin-key.pem

From here too, user jdoe is not supposed to get pods.

$ kubectl auth can-i get pods --as jdoe
no

Output of kubectl config view

$ kubectl config view 
apiVersion: v1
clusters:
- cluster:
    certificate-authority: /home/master/ca.pem
    server: https://192.168.1.111:6443
  name: jdoe
- cluster:
    certificate-authority-data: REDACTED
    server: https://192.168.1.111:6443
  name: kubernetes
- cluster:
    certificate-authority: /home/master/ca.pem
    server: https://192.168.1.111:6443
  name: master
contexts:
- context:
    cluster: jdoe
    user: jdoe
  name: jdoe
- context:
    cluster: kubernetes
    user: admin
  name: kubernetes
- context:
    cluster: master
    user: master
  name: master
current-context: kubernetes
kind: Config
preferences: {}
users:
- name: admin
  user:
    client-certificate: /home/master/admin.pem
    client-key: /home/master/admin-key.pem
- name: jdoe
  user:
    client-certificate: /home/master/jdoe.pem
    client-key: /home/master/jdoe-key.pem
- name: master
  user:
    client-certificate: /home/master/master.pem
    client-key: /home/master/master-key.pem