Always call rt_ifa_dellocal(9) when removing an IPv6 address.

The routing layer already check for the correct ifa when asked
to delete a local route, so do not try to be clever here.

This change also prevent having a NULL ifp pointer in your routing
table when you delete loopback interfaces having the same address.

ok henning@

diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index 5d90cee..85db120 100644 (file)
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: in6.c,v 1.154 2015/03/14 03:38:52 jsg Exp $   */
+/*     $OpenBSD: in6.c,v 1.155 2015/04/20 08:53:36 mpi Exp $   */
 /*     $KAME: in6.c,v 1.372 2004/06/14 08:14:21 itojun Exp $   */
 
 /*
@@ -1010,9 +1010,8 @@ void
 in6_purgeaddr(struct ifaddr *ifa)
 {
        struct ifnet *ifp = ifa->ifa_ifp;
-       struct in6_ifaddr *tmp, *ia6 = ifatoia6(ifa);
+       struct in6_ifaddr *ia6 = ifatoia6(ifa);
        struct in6_multi_mship *imm;
-       int ia6_count = 0;
 
        /* stop DAD processing */
        nd6_dad_stop(ifa);
@@ -1037,35 +1036,8 @@ in6_purgeaddr(struct ifaddr *ifa)
                        ia6->ia_flags &= ~IFA_ROUTE;
        }
 
-       /* Remove ownaddr's loopback rtentry, if it exists.
-        *
-        * Some of BSD variants do not remove cloned routes from an
-        * interface direct route, when removing the direct route (see
-        * comments in net/net_osdep.h).  Even for variants that do
-        * remove cloned routes, they could fail to remove the cloned
-        * routes when we handle multiple addresses that share a common
-        * prefix.  So, we should remove the route corresponding to the
-        * deleted address.
-        *
-        * Delete the entry only if exact one ifa exists.  More than one
-        * ifa can exist if we assign a same single address to multiple
-        * (probably p2p) interfaces.
-        * XXX: we should avoid such a configuration in IPv6...
-        */
-       TAILQ_FOREACH(tmp, &in6_ifaddr, ia_list) {
-               if (tmp->ia_ifp->if_rdomain != ifp->if_rdomain)
-                       continue;
-
-               if (IN6_ARE_ADDR_EQUAL(&tmp->ia_addr.sin6_addr,
-                   &ia6->ia_addr.sin6_addr)) {
-                       ia6_count++;
-                       if (ia6_count > 1)
-                               break;
-               }
-       }
-
-       if (ia6_count == 1)
-               rt_ifa_dellocal(&(ia6->ia_ifa));
+       /* Remove ownaddr's loopback rtentry, if it exists. */
+       rt_ifa_dellocal(&(ia6->ia_ifa));
 
        /*
         * leave from multicast groups we have joined for the interface