[src/trunk]: src/sys/net Fix to check whether the address has been added befo...

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

details:   https://anonhg.NetBSD.org/src/rev/32f0a08d2468
branches:  trunk
changeset: 323408:32f0a08d2468
user:      yamaguchi <yamaguchi%NetBSD.org@localhost>
date:      Thu Jun 14 08:33:18 2018 +0000

description:
Fix to check whether the address has been added before delete

The list named ifv_mc_listhead saves multicast addresses that
are added through SIOCADDMULTI. Each nodes added to the list
are used for deleting the related address from a parent I/F
when remove the configuration of parent I/F.
In carp(4) and OpenBSD's vlan(4), the lists is used to check
a parameter of SIOCDELMULTI in addition to the use.
Based on them, the check is added to vlan(4)

ok ozaki-r@

diffstat:

 sys/net/if_vlan.c |  31 ++++++++++++++++++-------------
 1 files changed, 18 insertions(+), 13 deletions(-)

diffs (67 lines):

diff -r c5cc4c524ac2 -r 32f0a08d2468 sys/net/if_vlan.c
--- a/sys/net/if_vlan.c Thu Jun 14 08:27:10 2018 +0000
+++ b/sys/net/if_vlan.c Thu Jun 14 08:33:18 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_vlan.c,v 1.128 2018/06/14 08:06:07 yamaguchi Exp $  */
+/*     $NetBSD: if_vlan.c,v 1.129 2018/06/14 08:33:18 yamaguchi Exp $  */
 
 /*
  * Copyright (c) 2000, 2001 The NetBSD Foundation, Inc.
@@ -78,7 +78,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_vlan.c,v 1.128 2018/06/14 08:06:07 yamaguchi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_vlan.c,v 1.129 2018/06/14 08:33:18 yamaguchi Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_inet.h"
@@ -1229,6 +1229,17 @@
        ETHER_LOCK(&ifv->ifv_ec);
        enm = ether_lookup_multi(addrlo, addrhi, &ifv->ifv_ec);
        ETHER_UNLOCK(&ifv->ifv_ec);
+       if (enm == NULL)
+               return EINVAL;
+
+       LIST_FOREACH(mc, &ifv->ifv_mc_listhead, mc_entries) {
+               if (mc->mc_enm == enm)
+                       break;
+       }
+
+       /* We woun't delete entries we didn't add */
+       if (mc == NULL)
+               return EINVAL;
 
        error = ether_delmulti(sa, &ifv->ifv_ec);
        if (error != ENETRESET)
@@ -1242,17 +1253,11 @@
 
        if (error == 0) {
                /* And forget about this address. */
-               for (mc = LIST_FIRST(&ifv->ifv_mc_listhead); mc != NULL;
-                   mc = LIST_NEXT(mc, mc_entries)) {
-                       if (mc->mc_enm == enm) {
-                               LIST_REMOVE(mc, mc_entries);
-                               free(mc, M_DEVBUF);
-                               break;
-                       }
-               }
-               KASSERT(mc != NULL);
-       } else
+               LIST_REMOVE(mc, mc_entries);
+               free(mc, M_DEVBUF);
+       } else {
                (void)ether_addmulti(sa, &ifv->ifv_ec);
+       }
 
        return error;
 }
@@ -1276,7 +1281,7 @@
        while ((mc = LIST_FIRST(&ifv->ifv_mc_listhead)) != NULL) {
                IFNET_LOCK(mib->ifvm_p);
                (void)if_mcast_op(mib->ifvm_p, SIOCDELMULTI,
-                   (const struct sockaddr *)&mc->mc_addr);
+                   sstocsa(&mc->mc_addr));
                IFNET_UNLOCK(mib->ifvm_p);
                LIST_REMOVE(mc, mc_entries);
                free(mc, M_DEVBUF);