Google Container Registry Service Account Permissions

21046548While testing Jenkins X I hit an issue that puzzled me. I use Kaniko to build Docker images and push them into Google Container Registry. But the push to GCR was failing with

INFO[0000] Taking snapshot of files...
error pushing image: failed to push to destination gcr.io/myprojectid/croc-hunter:1: DENIED: Token exchange failed for project 'myprojectid'. Caller does not have permission 'storage.buckets.get'. To configure permissions, follow instructions at: https://cloud.google.com/container-registry/docs/access-control

During installation Jenkins X creates a GCP Service Account based on the name of the cluster (in my case jx-rocks) called jxkaniko-jx-rocks with roles:

  • roles/storage.admin
  • roles/storage.objectAdmin
  • roles/storage.objectCreator

More roles are added if you install Jenkins X with Vault enabled.

A key is created for the service account and added to Kubernetes as secrets/kaniko-secret containing the service account key json, which is later on mounted in the pods running Kaniko as described in their instructions.

After looking and looking the service account and roles they all seemed correct in the GCP console, but the Kaniko build was still failing. I found a stackoverflow post claiming that the permissions were cached if you had a previous service account with the same name (WAT?), so I tried with a new service account with same permissions and different name and that worked. Weird. So I created a script to replace the service account by another one and update the Kubernetes secret.

ACCOUNT=jxkaniko-jx-rocks
PROJECT_ID=myprojectid

# delete the existing service account and policy binding
gcloud -q iam service-accounts delete ${ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com
gcloud -q projects remove-iam-policy-binding ${PROJECT_ID} --member=serviceAccount:${ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com --role roles/storage.admin
gcloud -q projects remove-iam-policy-binding ${PROJECT_ID} --member=serviceAccount:${ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com --role roles/storage.objectAdmin
gcloud -q projects remove-iam-policy-binding ${PROJECT_ID} --member=serviceAccount:${ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com --role roles/storage.objectCreator

# create a new one
gcloud -q iam service-accounts create ${ACCOUNT} --display-name ${ACCOUNT}
gcloud -q projects add-iam-policy-binding ${PROJECT_ID} --member=serviceAccount:${ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com --role roles/storage.admin
gcloud -q projects add-iam-policy-binding ${PROJECT_ID} --member=serviceAccount:${ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com --role roles/storage.objectAdmin
gcloud -q projects add-iam-policy-binding ${PROJECT_ID} --member=serviceAccount:${ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com --role roles/storage.objectCreator

# create a key for the service account and update the secret in Kubernetes
gcloud -q iam service-accounts keys create kaniko-secret --iam-account=${ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com
kubectl create secret generic kaniko-secret --from-file=kaniko-secret

And it did also work, so no idea why it was failing, but at least I’ll remember now how to manually cleanup and recreate the service account.