The usual way to update the ownerships and/or permissions of an actual mountpoint directory is to unmount the filesystem, then update its attributes and then re-mount it back to its original location. However this is not always possible or desireable. Instead following workaround can be used on a live mountpoint.
This can be done by temporarily sharing the
/ via NFS and re-mouting the mountpoint in a temporary location:
Then update permissions and/or ownerships:
Finally unshare the