diff --git a/kernel/sys.c b/kernel/sys.c
index 0f45fb855fe3..66b933a5c061 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2220,11 +2220,11 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
 		error = prctl_get_tid_address(me, (int __user **)arg2);
 		break;
 	case PR_SET_TIMERSLACK_PID:
-		if (current->pid != (pid_t)arg3 &&
+		if (task_pid_vnr(current) != (pid_t)arg3 &&
 				!capable(CAP_SYS_NICE))
 			return -EPERM;
 		rcu_read_lock();
-		tsk = find_task_by_pid_ns((pid_t)arg3, &init_pid_ns);
+		tsk = find_task_by_vpid((pid_t)arg3);
 		if (tsk == NULL) {
 			rcu_read_unlock();
 			return -EINVAL;