From 060157415d5f0558d2a599bcd4ad9c3bcfe5d570 Mon Sep 17 00:00:00 2001
From: akoshibe <akoshibe@openbsd.org>
Date: Thu, 9 Aug 2018 03:35:19 +0000
Subject: [PATCH] Currently, attempting to move an immovable lo(4) to a new
 rdomain will fail with an EPERM, but the target rdomain will still be
 created.

Move the check for an lo(4)'s if_index/if_rdomain to before the creation of a
nonexisting target routing table.

ok benno@ claudio@ mpi@
---
 sys/net/if.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/sys/net/if.c b/sys/net/if.c
index e6546dff224..7097eb278ef 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.c,v 1.558 2018/07/11 09:08:21 henning Exp $	*/
+/*	$OpenBSD: if.c,v 1.559 2018/08/09 03:35:19 akoshibe Exp $	*/
 /*	$NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $	*/
 
 /*
@@ -1743,6 +1743,10 @@ if_setrdomain(struct ifnet *ifp, int rdomain)
 	if (rdomain < 0 || rdomain > RT_TABLEID_MAX)
 		return (EINVAL);
 
+	if ((ifp->if_flags & IFF_LOOPBACK) &&
+	    (ifp->if_index == rtable_loindex(ifp->if_rdomain)))
+		return (EPERM);
+
 	/*
 	 * Create the routing table if it does not exist, including its
 	 * loopback interface with unit == rdomain.
@@ -1777,10 +1781,6 @@ if_setrdomain(struct ifnet *ifp, int rdomain)
 		return (EINVAL);
 
 	if (rdomain != ifp->if_rdomain) {
-		if ((ifp->if_flags & IFF_LOOPBACK) &&
-		    (ifp->if_index == rtable_loindex(ifp->if_rdomain)))
-			return (EPERM);
-
 		s = splnet();
 		/*
 		 * We are tearing down the world.
-- 
2.20.1