From 2ca83196824beceded07891c8df42108b03790f5 Mon Sep 17 00:00:00 2001
From: mpi <mpi@openbsd.org>
Date: Tue, 13 Oct 2015 10:21:27 +0000
Subject: [PATCH] Simplify arptfree() to no longer look at the route entry's
 refcounter.

ARP entries with an expired timeout are now removed from the tree even
if they are cached somehwere else.  This also reduces differences with
NDP.

ok bluhm@
---
 sys/netinet/if_ether.c | 25 ++++++++-----------------
 1 file changed, 8 insertions(+), 17 deletions(-)

diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index 9c9f617c54e..1b834ef2238 100644
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ether.c,v 1.171 2015/10/07 08:58:01 mpi Exp $	*/
+/*	$OpenBSD: if_ether.c,v 1.172 2015/10/13 10:21:27 mpi Exp $	*/
 /*	$NetBSD: if_ether.c,v 1.31 1996/05/11 12:59:58 mycroft Exp $	*/
 
 /*
@@ -91,7 +91,7 @@ int	arpt_prune = (5*60*1);	/* walk list every 5 minutes */
 int	arpt_keep = (20*60);	/* once resolved, good for 20 more minutes */
 int	arpt_down = 20;		/* once declared down, don't send for 20 secs */
 
-void arptfree(struct llinfo_arp *);
+void arptfree(struct rtentry *);
 void arptimer(void *);
 struct rtentry *arplookup(u_int32_t, int, int, u_int);
 void in_arpinput(struct mbuf *);
@@ -133,7 +133,7 @@ arptimer(void *arg)
 
 		nla = LIST_NEXT(la, la_list);
 		if (rt->rt_expire && rt->rt_expire <= time_second)
-			arptfree(la); /* timer has expired; clear */
+			arptfree(rt); /* timer has expired; clear */
 	}
 	splx(s);
 }
@@ -772,26 +772,17 @@ out:
  * Free an arp entry.
  */
 void
-arptfree(struct llinfo_arp *la)
+arptfree(struct rtentry *rt)
 {
-	struct rtentry *rt = la->la_rt;
-	struct sockaddr_dl *sdl;
-	u_int tid = 0;
+	struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
+	struct sockaddr_dl *sdl = SDL(rt->rt_gateway);
 
-	if (rt == NULL)
-		panic("arptfree");
-	if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
-	    sdl->sdl_family == AF_LINK) {
+	if ((sdl != NULL) && (sdl->sdl_family == AF_LINK)) {
 		sdl->sdl_alen = 0;
 		la->la_asked = 0;
-		rt->rt_flags &= ~RTF_REJECT;
-		return;
 	}
 
-	if (rt->rt_ifp)
-		tid = rt->rt_ifp->if_rdomain;
-
-	rtdeletemsg(rt, tid);
+	rtdeletemsg(rt, rt->rt_ifp->if_rdomain);
 }
 
 /*
-- 
2.20.1