[src/trunk]: src/sys/netinet When changing an address via in_ifinit, ensure t...

[roy <roy%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/f5d60d58e3b6
branches:  trunk
changeset: 347997:f5d60d58e3b6
user:      roy <roy%NetBSD.org@localhost>
date:      Thu Sep 29 14:18:38 2016 +0000

description:
When changing an address via in_ifinit, ensure that the old address
is correctly scrubbed.
This allows sppp consumers to announce removal of the old address.

diffstat:

 sys/netinet/in.c |  41 +++++++++++++++++++++++++++--------------
 1 files changed, 27 insertions(+), 14 deletions(-)

diffs (98 lines):

diff -r cf9c3d6f8d2c -r f5d60d58e3b6 sys/netinet/in.c
--- a/sys/netinet/in.c  Thu Sep 29 14:08:40 2016 +0000
+++ b/sys/netinet/in.c  Thu Sep 29 14:18:38 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: in.c,v 1.182 2016/09/16 14:17:23 roy Exp $     */
+/*     $NetBSD: in.c,v 1.183 2016/09/29 14:18:38 roy Exp $     */
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -91,7 +91,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: in.c,v 1.182 2016/09/16 14:17:23 roy Exp $");
+__KERNEL_RCSID(0, "$NetBSD: in.c,v 1.183 2016/09/29 14:18:38 roy Exp $");
 
 #include "arp.h"
 
@@ -149,6 +149,7 @@
        struct ifnet *);
 
 static int     in_addprefix(struct in_ifaddr *, int);
+static void    in_scrubaddr(struct in_ifaddr *);
 static int     in_scrubprefix(struct in_ifaddr *);
 static void    in_sysctl_init(struct sysctllog **);
 
@@ -799,6 +800,22 @@
        curlwp_bindx(bound);
 }
 
+static void
+in_scrubaddr(struct in_ifaddr *ia)
+{
+
+       /* stop DAD processing */
+       if (ia->ia_dad_stop != NULL)
+               ia->ia_dad_stop(&ia->ia_ifa);
+
+       in_ifscrub(ia->ia_ifp, ia);
+       in_ifremlocal(&ia->ia_ifa);
+       if (ia->ia_allhosts != NULL) {
+               in_delmulti(ia->ia_allhosts);
+               ia->ia_allhosts = NULL;
+       }
+}
+
 /*
  * Depends on it isn't called in concurrent. It should be guaranteed
  * by ifa->ifa_ifp's ioctl lock. The possible callers are in_control
@@ -809,19 +826,12 @@
 void
 in_purgeaddr(struct ifaddr *ifa)
 {
+       struct in_ifaddr *ia = (void *) ifa;
        struct ifnet *ifp = ifa->ifa_ifp;
-       struct in_ifaddr *ia = (void *) ifa;
 
        KASSERT(!ifa_held(ifa));
 
-       /* stop DAD processing */
-       if (ia->ia_dad_stop != NULL)
-               ia->ia_dad_stop(ifa);
-
-       in_ifscrub(ifp, ia);
-       in_ifremlocal(ifa);
-       if (ia->ia_allhosts != NULL)
-               in_delmulti(ia->ia_allhosts);
+       in_scrubaddr(ia);
 
        mutex_enter(&in_ifaddr_lock);
        LIST_REMOVE(ia, ia_hash);
@@ -1098,12 +1108,15 @@
                return error;
        }
 
-       if (scrub) {
+       if (scrub || hostIsNew) {
                int newflags = ia->ia4_flags;
 
                ia->ia_ifa.ifa_addr = sintosa(&oldaddr);
                ia->ia4_flags = oldflags;
-               in_ifscrub(ifp, ia);
+               if (hostIsNew)
+                       in_scrubaddr(ia);
+               else if (scrub)
+                       in_ifscrub(ifp, ia);
                ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
                ia->ia4_flags = newflags;
        }
@@ -1248,7 +1261,7 @@
        int error;
        int s;
 
-       /* If we don't have IFA_ROUTE we should still inform userland */
+       /* If we don't have IFA_ROUTE we have nothing to do */
        if ((target->ia_flags & IFA_ROUTE) == 0)
                return 0;