SMB + SMB2: Accessing shares return an error after prolonged idle period

Issue

• After a period of inactivity, accessing a SMB v1 share returns Permission denied for a user, but not others
• After a period of inactivity, accessing a SMB v2+ share returns Input/output error for a user, but not others.
• The following error may be returned in the logs: CIFS VFS: Unexpected lookup error -5
• Periodically accessing a share avoids the errors.
• Shares have to be unmounted and then remounted to regain access.