GitLab Runner OpenShift error: could not lock config file //.gitconfig: Permission denied

Summary

Summarize the bug encountered concisely

GitLab runner with kubernetes executor wont work with privileged = false container option .

Steps to reproduce

Configure GitLab runner for working with RH OpenShift platform , configmap :

  - kind: "ConfigMap"
    apiVersion: v1
    metadata:
      name: "${APP_NAME}"
      namespace: "${NAMESPACE}"
    data:
      config.toml: |
        concurrent = 1
        check_interval = 0

        [[runners]]
          name = "openshift"
          url = "https://gitlab.consto.com/"
          token = "${TOKEN}"
          executor = "kubernetes"
          [runners.cache]
          [runners.kubernetes]
            service-account = "runner-sa"
            bearer_token_overwrite_allowed = true
            image = ""
            namespace = "${NAMESPACE}"
            namespace_overwrite_allowed = ""
            privileged = false
            service_account_overwrite_allowed = ""
            pod_annotations_overwrite_allowed = ""

SCC for service account runner-sa:

  - kind: "SecurityContextConstraints"
    apiVersion: v1
    metadata:
      name: gitlab-runner
    allowPrivilegedContainer: yes
    runAsUser:
      type: RunAsAny
    seLinuxContext:
      type: RunAsAny
    fsGroup:
      type: RunAsAny
    supplementalGroups:
      type: RunAsAny

    allowHostDirVolumePlugin: true

    users:
    - system:serviceaccount:${NAMESPACE}:runner-sa

Pipelines running only if option privileged has true value , else I get error : error: could not lock config file //.gitconfig: Permission denied

Actual behavior

What actually happens

Expected behavior

GitLab runner working with not privileged mode .

Relevant logs and/or screenshots

Running with gitlab-runner 11.1.0 (081978aa)
  on openshift ff568bcd
"BearerToken" overwritten with "XXXXXXXX..."
Using Kubernetes namespace: building-base-images
Using Kubernetes executor with image docker-registry.consto.com/openshift3/ose-ansible:latest ...
Waiting for pod building-base-images/runner-ff568bcd-project-20-concurrent-05qvzr to be running, status is Pending
Waiting for pod building-base-images/runner-ff568bcd-project-20-concurrent-05qvzr to be running, status is Pending
Running on runner-ff568bcd-project-20-concurrent-05qvzr via gitlab-runner-01-18-s9klb...
error: could not lock config file //.gitconfig: Permission denied
ERROR: Job failed: command terminated with exit code 1

Environment description

openshift 3.10 gitlab ee 11.0.3-ee (f25aa33)

Used GitLab Runner version

gitlab-runner 11.1.0 (081978aa)