Merge common code into new nd6_dad_destroy()

The current code wrt. stopping DAD for and removing a particular IP from
the list is flawed.

Introduce a single nd6_dad_destroy() to the cleanup, so that there's
only one place to fix.

This is just a mechanical deduplication without significant behaviour
change;  in case a duplicated address was found, RTM_CHGADDRATTR now goes
out before cleanup, which should be no problem.

The nd6_dad_create() pendant could be done as well, but the end of
nd6_dad_start() is currently the only place where a new IP/DAD entry is
set up, so little gain besides function name symmetry.

OK claudio

diff --git a/sys/netinet6/nd6_nbr.c b/sys/netinet6/nd6_nbr.c
index 6dffeda..4dd2f4b 100644 (file)
--- a/sys/netinet6/nd6_nbr.c
+++ b/sys/netinet6/nd6_nbr.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: nd6_nbr.c,v 1.141 2022/12/10 21:29:10 mvs Exp $       */
+/*     $OpenBSD: nd6_nbr.c,v 1.142 2023/01/06 14:17:15 kn Exp $        */
 /*     $KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 jinmei Exp $        */
 
 /*
@@ -76,6 +76,7 @@ struct dadq {
 };
 
 struct dadq *nd6_dad_find(struct ifaddr *);
+void nd6_dad_destroy(struct dadq *);
 void nd6_dad_starttimer(struct dadq *);
 void nd6_dad_stoptimer(struct dadq *);
 void nd6_dad_timer(void *);
@@ -1047,6 +1048,15 @@ nd6_dad_find(struct ifaddr *ifa)
        return NULL;
 }
 
+void
+nd6_dad_destroy(struct dadq *dp)
+{
+       TAILQ_REMOVE(&dadq, dp, dad_list);
+       ifafree(dp->dad_ifa);
+       free(dp, M_IP6NDP, sizeof(*dp));
+       ip6_dad_pending--;
+}
+
 void
 nd6_dad_starttimer(struct dadq *dp)
 {
@@ -1135,12 +1145,7 @@ nd6_dad_stop(struct ifaddr *ifa)
        }
 
        nd6_dad_stoptimer(dp);
-
-       TAILQ_REMOVE(&dadq, dp, dad_list);
-       free(dp, M_IP6NDP, sizeof(*dp));
-       dp = NULL;
-       ifafree(ifa);
-       ip6_dad_pending--;
+       nd6_dad_destroy(dp);
 }
 
 void
@@ -1183,11 +1188,7 @@ nd6_dad_timer(void *xifa)
                nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n",
                        ifa->ifa_ifp->if_xname));
 
-               TAILQ_REMOVE(&dadq, dp, dad_list);
-               free(dp, M_IP6NDP, sizeof(*dp));
-               dp = NULL;
-               ifafree(ifa);
-               ip6_dad_pending--;
+               nd6_dad_destroy(dp);
                goto done;
        }
 
@@ -1219,11 +1220,7 @@ nd6_dad_timer(void *xifa)
                            inet_ntop(AF_INET6, &ia6->ia_addr.sin6_addr,
                                addr, sizeof(addr))));
 
-                       TAILQ_REMOVE(&dadq, dp, dad_list);
-                       free(dp, M_IP6NDP, sizeof(*dp));
-                       dp = NULL;
-                       ifafree(ifa);
-                       ip6_dad_pending--;
+                       nd6_dad_destroy(dp);
                }
        }
 
@@ -1255,13 +1252,9 @@ nd6_dad_duplicated(struct dadq *dp)
        log(LOG_ERR, "%s: manual intervention required\n",
            ia6->ia_ifp->if_xname);
 
-       TAILQ_REMOVE(&dadq, dp, dad_list);
-
        rtm_addr(RTM_CHGADDRATTR, dp->dad_ifa);
 
-       ifafree(dp->dad_ifa);
-       free(dp, M_IP6NDP, sizeof(*dp));
-       ip6_dad_pending--;
+       nd6_dad_destroy(dp);
 }
 
 void