Why do file permissions appear incorrectly with Linux SMB?
The mount command will determine a default set of permissions for owner and group permissions in Linux. This “default” set of permissions appears to be applied to all the files, but the real file permissions are not displayed. Likewise, if you change permissions on DCShome files/directories through an SMB mount, the real file permissions are not changed, only the appearance of the default set of permissions are changed. As soon as the volume is umounted and re-mounted through smbfs/cifs, the permissions will appear to be the default set specified in the mount command.