Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933801Ab3DBWgm (ORCPT ); Tue, 2 Apr 2013 18:36:42 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:33282 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933500Ab3DBWNK (ORCPT ); Tue, 2 Apr 2013 18:13:10 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hannes Frederic Sowa , Erik Hugne , YOSHIFUJI Hideaki , "David S. Miller" Subject: [ 117/124] ipv6: dont accept node local multicast traffic from the wire Date: Tue, 2 Apr 2013 15:11:39 -0700 Message-Id: <20130402221117.720986532@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130402221104.163133110@linuxfoundation.org> References: <20130402221104.163133110@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2058 Lines: 55 3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hannes Frederic Sowa [ Upstream commit 1c4a154e5253687c51123956dfcee9e9dfa8542d ] Erik Hugne's errata proposal (Errata ID: 3480) to RFC4291 has been verified: http://www.rfc-editor.org/errata_search.php?eid=3480 We have to check for pkt_type and loopback flag because either the packets are allowed to travel over the loopback interface (in which case pkt_type is PACKET_HOST and IFF_LOOPBACK flag is set) or they travel over a non-loopback interface back to us (in which case PACKET_TYPE is PACKET_LOOPBACK and IFF_LOOPBACK flag is not set). Signed-off-by: Hannes Frederic Sowa Cc: Erik Hugne Cc: YOSHIFUJI Hideaki Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_input.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -118,6 +118,18 @@ int ipv6_rcv(struct sk_buff *skb, struct ipv6_addr_loopback(&hdr->daddr)) goto err; + /* RFC4291 Errata ID: 3480 + * Interface-Local scope spans only a single interface on a + * node and is useful only for loopback transmission of + * multicast. Packets with interface-local scope received + * from another node must be discarded. + */ + if (!(skb->pkt_type == PACKET_LOOPBACK || + dev->flags & IFF_LOOPBACK) && + ipv6_addr_is_multicast(&hdr->daddr) && + IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 1) + goto err; + /* RFC4291 2.7 * Nodes must not originate a packet to a multicast address whose scope * field contains the reserved value 0; if such a packet is received, it -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/