From the mailing list I have a Debian Buster member server which I upgraded to version 4.14.0 and since then I have been getting several log messages like this one in syslog: Mar 13 10:33:34 lxd-m1 smbd[1406]: filename_convert_internal: open_pathref_fsp [roy] failed: NT_STATUS_ACCESS_DENIED Have patch, need bugnumber.
This bug was referenced in samba master: 11aac9d0433ab59740c40712c3782f1cf4ac0418