From adad83c7fcbb2a8f3108ab8f10e94e099cf6951e Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 18 Mar 2003 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 2003-03-18

---
 ip/arp.c   | 8 ++++----
 ip/ip.c    | 3 ++-
 ip/ipifc.c | 9 +++++++++
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/ip/arp.c b/ip/arp.c
index 7a52711fa549d93df9ec25c3eb4001cb5534202b..6e25de730b99b0d0094694d9bd2641cb021ffb68 100644
--- a/ip/arp.c
+++ b/ip/arp.c
@@ -125,7 +125,7 @@ newarp6(Arp *arp, uchar *ip, Ipifc *ifc, int addrxt)
 
 	memmove(a->ip, ip, sizeof(a->ip));
 	a->utime = NOW;
-	a->ctime = a->utime;
+	a->ctime = 0;
 	a->type = m;
 
 	a->rtime = NOW + ReTransTimer;
@@ -354,14 +354,16 @@ arpenter(Fs *fs, int version, uchar *ip, uchar *mac, int n, int refresh)
 				}
 			}
 
-			a->hold = nil;
 			a->ifc = ifc;
 			a->ifcid = ifc->ifcid;
 			bp = a->hold;
 			a->hold = nil;
 			if(version == V4)
 				ip += IPv4off;
+			a->utime = NOW;
+			a->ctime = a->utime;
 			qunlock(arp);
+
 			while(bp){
 				next = bp->list;
 				if(ifc != nil){
@@ -380,8 +382,6 @@ arpenter(Fs *fs, int version, uchar *ip, uchar *mac, int n, int refresh)
 					freeb(bp);
 				bp = next;
 			}
-			a->utime = NOW;
-			a->ctime = a->utime;
 			return;
 		}
 	}
diff --git a/ip/ip.c b/ip/ip.c
index 24062946909f0c963942781201e8c5454ebc39b0..2936ce1f6f7fa8ee673efa7bdf2822bdf97387b4 100644
--- a/ip/ip.c
+++ b/ip/ip.c
@@ -486,7 +486,7 @@ ipiput4(Fs *f, Ipifc *ifc, Block *bp)
 		/* don't forward to source's network */
 		conv.r = nil;
 		r = v4lookup(f, h->dst, &conv);
-		if(r != nil && r->ifc == ifc){
+		if(r == nil || r->ifc == ifc){
 			ip->stats[OutDiscards]++;
 			freeblist(bp);
 			return;
@@ -502,6 +502,7 @@ ipiput4(Fs *f, Ipifc *ifc, Block *bp)
 		}
 
 		/* reassemble if the interface expects it */
+if(r->ifc == nil) panic("nil route rfc");
 		if(r->ifc->reassemble){
 			frag = nhgets(h->frag);
 			if(frag) {
diff --git a/ip/ipifc.c b/ip/ipifc.c
index 003c719beab45473d851f520db7cc2bfa932d30b..bb92e29faef99414d57fddb9175142c18085b023 100644
--- a/ip/ipifc.c
+++ b/ip/ipifc.c
@@ -305,10 +305,19 @@ ipifckick(void *x)
 		return;
 
 	ifc = (Ipifc*)c->ptcl;
+	if(!canrlock(ifc)){
+		freeb(bp);
+		return;
+	}
+	if(waserror()){
+		runlock(ifc);
+		nexterror();
+	}
 	if(ifc->m == nil || ifc->m->pktin == nil)
 		freeb(bp);
 	else
 		(*ifc->m->pktin)(c->p->f, ifc, bp);
+	runlock(ifc);
 }
 
 /*