[src/trunk]: src/sys/net Purge L2 caches on changing an interface of a route

[ozaki-r <ozaki-r%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e77ff9b2d047
branches:  trunk
changeset: 824883:e77ff9b2d047
user:      ozaki-r <ozaki-r%NetBSD.org@localhost>
date:      Thu Jun 22 09:58:04 2017 +0000

description:
Purge L2 caches on changing an interface of a route

The change addresses situations similar to PR 51179.

diffstat:

 sys/net/rtsock.c |  16 ++++++++++++----
 1 files changed, 12 insertions(+), 4 deletions(-)

diffs (57 lines):

diff -r 926e26976ecb -r e77ff9b2d047 sys/net/rtsock.c
--- a/sys/net/rtsock.c  Thu Jun 22 09:56:48 2017 +0000
+++ b/sys/net/rtsock.c  Thu Jun 22 09:58:04 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rtsock.c,v 1.216 2017/06/16 02:26:17 ozaki-r Exp $     */
+/*     $NetBSD: rtsock.c,v 1.217 2017/06/22 09:58:04 ozaki-r Exp $     */
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -61,7 +61,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rtsock.c,v 1.216 2017/06/16 02:26:17 ozaki-r Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rtsock.c,v 1.217 2017/06/22 09:58:04 ozaki-r Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_inet.h"
@@ -641,7 +641,7 @@
        struct ifnet *ifp = NULL, *new_ifp;
        struct ifaddr *ifa = NULL, *new_ifa;
        struct psref psref_ifa, psref_new_ifa, psref_ifp;
-       bool newgw;
+       bool newgw, ifp_changed = false;
 
        /*
         * New gateway could require new ifaddr, ifp;
@@ -691,13 +691,16 @@
                                oifa->ifa_rtrequest(RTM_DELETE, rt, info);
                        rt_replace_ifa(rt, ifa);
                        rt->rt_ifp = new_ifp;
+                       ifp_changed = true;
                }
                if (new_ifa == NULL)
                        ifa_release(ifa, &psref_ifa);
        }
        ifa_release(new_ifa, &psref_new_ifa);
-       if (new_ifp && rt->rt_ifp != new_ifp && !if_is_deactivated(new_ifp))
+       if (new_ifp && rt->rt_ifp != new_ifp && !if_is_deactivated(new_ifp)) {
                rt->rt_ifp = new_ifp;
+               ifp_changed = true;
+       }
        rt_setmetrics(rtm->rtm_inits, rtm, rt);
        if (rt->rt_flags != info->rti_flags) {
                rt->rt_flags = (info->rti_flags & ~PRESERVED_RTF) |
@@ -705,6 +708,11 @@
        }
        if (rt->rt_ifa && rt->rt_ifa->ifa_rtrequest)
                rt->rt_ifa->ifa_rtrequest(RTM_ADD, rt, info);
+#if defined(INET) || defined(INET6)
+       if (ifp_changed && rt_mask(rt) != NULL)
+               lltable_prefix_free(rt_getkey(rt)->sa_family, rt_getkey(rt),
+                   rt_mask(rt), 0);
+#endif
 out:
        if_put(ifp, &psref_ifp);