From 2b0bb01b6edb3e13c7f71e43bf3a173a795b7b66 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Mon, 22 Sep 2014 10:07:24 +0200
Subject: [PATCH] ip6_tunnel: Return an error when adding an existing tunnel.
ip6_tnl_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 <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/ipv6/ip6_tunnel.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index f9de5a6950725..69a84b464009c 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -364,8 +364,12 @@ static struct ip6_tnl *ip6_tnl_locate(struct net *net,
(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;