SIDGROUP
rc = sid_to_id(cifs_sb, group_sid_ptr, fattr, SIDGROUP);
rc = id_to_sid(id, SIDGROUP, ngroup_sid_ptr);
sid_to_id(cifs_sb, &data->posix_group, fattr, SIDGROUP);
sid_to_id(cifs_sb, &parsed.group, fattr, SIDGROUP);