From 94daac47a198604080fb419f5adca43782163a05 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 3 Aug 1999 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1999-08-03

---
 ip/ipifc.c       | 13 ++++++++++---
 port/devbridge.c |  8 +++++---
 port/devroot.c   |  2 +-
 3 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/ip/ipifc.c b/ip/ipifc.c
index a194490e0a94a98f7596d28eb09d58d2bd6d2002..54778e0dd2b5302e2eaba2f79475d1f6b5ccc69a 100644
--- a/ip/ipifc.c
+++ b/ip/ipifc.c
@@ -1244,6 +1244,7 @@ ipifcregisterproxy(Fs *f, Ipifc *ifc, uchar *ip)
 	Conv **cp, **e;
 	Ipifc *nifc;
 	Iplifc *lifc;
+	Medium *m;
 	uchar net[IPaddrlen];
 
 	/* register the address on any network that will proxy for us */
@@ -1252,16 +1253,22 @@ ipifcregisterproxy(Fs *f, Ipifc *ifc, uchar *ip)
 		if(*cp == nil)
 			continue;
 		nifc = (Ipifc*)(*cp)->ptcl;
-		if(nifc->m->areg == nil)
-			continue;
 		if(nifc == ifc)
 			continue;
+
+		rlock(nifc);
+		m = nifc->m;
+		if(m == nil || m->areg == nil){
+			runlock(nifc);
+			continue;
+		}
 		for(lifc = nifc->lifc; lifc; lifc = lifc->next){
 			maskip(ip, lifc->mask, net);
 			if(ipcmp(net, lifc->remote) == 0){
-				(*nifc->m->areg)(nifc, ip);
+				(*m->areg)(nifc, ip);
 				break;
 			}
 		}
+		runlock(nifc);
 	}
 }
diff --git a/port/devbridge.c b/port/devbridge.c
index b6f3ec81968310ed08406e18cc751f9f314a229e..7eefe8785b17e36c791839549301c441e8c45ddd 100644
--- a/port/devbridge.c
+++ b/port/devbridge.c
@@ -799,7 +799,7 @@ etherread(void *a)
 	Block *bp, *bp2;
 	Etherpkt *ep;
 	Centry *ce;
-
+static uchar tribble[Eaddrlen] = {0x00, 0xd1, 0x80, 0xaa, 0xbb, 0x07};
 	
 	qlock(b);
 	port->readp = up;	/* hide identity under a rock for unbind */
@@ -841,8 +841,10 @@ etherread(void *a)
 			if(ce == nil) {
 				b->miss++;
 				port->inunknown++;
-				bp2 = bp; bp = nil;
-				ethermultiwrite(b, bp2, port);
+				if(port->type != Tether || memcmp(ep->s, tribble, Eaddrlen) == 0) {
+					bp2 = bp; bp = nil;
+					ethermultiwrite(b, bp2, port);
+				}	
 			} else if (ce->port != port->id) {
 				b->hit++;
 				bp2 = bp; bp = nil;
diff --git a/port/devroot.c b/port/devroot.c
index a2df3d8f377cdda2951ca67dda58d697c22e491f..dd299f09b5749fb2cdc7d76220f06efba897d2f1 100644
--- a/port/devroot.c
+++ b/port/devroot.c
@@ -76,7 +76,7 @@ addrootfile(char *name, uchar *contents, ulong len)
 static void
 addrootdir(char *name)
 {
-	addroot(name, nil, 0, CHDIR);
+	addroot(name, nil, 0, CHDIR|0555);
 }
 
 static void