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| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2013-03-26 08:13:34 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-03-29 14:57:33 -0400 |
| commit | 1c4a154e5253687c51123956dfcee9e9dfa8542d (patch) | |
| tree | b1474cc86d41df9590269723d6c6060be44bdb3a /net | |
| parent | 74f9f42c1c1650e74fb464f76644c9041f996851 (diff) | |
| download | lwn-1c4a154e5253687c51123956dfcee9e9dfa8542d.tar.gz lwn-1c4a154e5253687c51123956dfcee9e9dfa8542d.zip | |
ipv6: don't accept node local multicast traffic from the wire
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 <erik.hugne@ericsson.com>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/ip6_input.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index e33fe0ab2568..2bab2aa59745 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -118,6 +118,18 @@ 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 |