Cause: open-behind delaying the open calls
Consequence: in fuse when root-squash is enabled, the file can be read even though it does not have read permissions
i.e root requests will be converted to nfsnobody and as per the file permissions nfsnobody does not have the read permission.
Workaround (if any): Turn off open-behind
Result: With open-behind turned off it behaves properly i.e file with no read permissions for others cannot be read upon requests getting root-squashed.