set_user          622 kernel/sys.c   	if (new_ruid != old_ruid && set_user(new_ruid, new_euid != old_euid) < 0)
set_user          669 kernel/sys.c   		if (uid != old_ruid && set_user(uid, old_euid != uid) < 0)
set_user          716 kernel/sys.c   		if (ruid != current->uid && set_user(ruid, euid != current->euid) < 0)