From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steffen Klassert Subject: [PATCH net 3/3] ip6_gre: Return an error when adding an existing tunnel. Date: Mon, 22 Sep 2014 10:07:26 +0200 Message-ID: <1411373246-22389-4-git-send-email-steffen.klassert@secunet.com> References: <1411373246-22389-1-git-send-email-steffen.klassert@secunet.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Steffen Klassert , To: David Miller Return-path: Received: from a.mx.secunet.com ([195.81.216.161]:53884 "EHLO a.mx.secunet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752984AbaIVIHp (ORCPT ); Mon, 22 Sep 2014 04:07:45 -0400 In-Reply-To: <1411373246-22389-1-git-send-email-steffen.klassert@secunet.com> Sender: netdev-owner@vger.kernel.org List-ID: ip6gre_tunnel_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 --- net/ipv6/ip6_gre.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 5f19dfb..2e5a882 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -314,6 +314,8 @@ static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE); + if (t && create) + return NULL; if (t || !create) return t; -- 1.9.1