ip6_vti: Return an error when adding an existing tunnel.

vti6_locate() should not return an existing tunnel if create is true. Otherwise it is possible to add the same tunnel multiple times without getting an error. So return NULL if the tunnel that should be created already exists. Signed-off-by: Steffen Klassert <[email protected]> Signed-off-by: David S. Miller <[email protected]>
cbmeeks · Sep 28, 2014 · d814b84 · d814b84
1 parent 2b0bb01
commit d814b84
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
@@ -253,8 +253,12 @@ static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
 	     (t = rtnl_dereference(*tp)) != NULL;
 	     tp = &t->next) {
 		if (ipv6_addr_equal(local, &t->parms.laddr) &&
-		    ipv6_addr_equal(remote, &t->parms.raddr))
+		    ipv6_addr_equal(remote, &t->parms.raddr)) {
+			if (create)
+				return NULL;
+
 			return t;
+		}
 	}
 	if (!create)
 		return NULL;