Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935889Ab3DHJwi (ORCPT ); Mon, 8 Apr 2013 05:52:38 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42972 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935853Ab3DHJwe (ORCPT ); Mon, 8 Apr 2013 05:52:34 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Erik Hugne , YOSHIFUJI Hideaki , Hannes Frederic Sowa , "David S. Miller" , Luis Henriques Subject: [PATCH 077/102] ipv6: don't accept node local multicast traffic from the wire Date: Mon, 8 Apr 2013 10:50:32 +0100 Message-Id: <1365414657-29191-78-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1365414657-29191-1-git-send-email-luis.henriques@canonical.com> References: <1365414657-29191-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2194 Lines: 57 3.5.7.10 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Hannes Frederic Sowa commit 1c4a154e5253687c51123956dfcee9e9dfa8542d upstream. 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). Cc: Erik Hugne Cc: YOSHIFUJI Hideaki Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller Signed-off-by: Luis Henriques --- net/ipv6/ip6_input.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index 311eac7..594a4ec 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -111,6 +111,18 @@ int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt 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 -- 1.8.1.2 -- 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/