From 20314092c1b41894d8c181bf9aa6f022be2416aa Mon Sep 17 00:00:00 2001 From: Hannes Frederic Sowa Date: Sun, 10 Feb 2013 05:35:22 +0000 Subject: [PATCH] ipv6: don't accept multicast traffic with scope 0 v2: a) moved before multicast source address check b) changed comment to netdev style Cc: Erik Hugne Cc: YOSHIFUJI Hideaki Acked-by: YOSHIFUJI Hideaki Signed-off-by: Hannes Frederic Sowa Acked-by: YOSHIFUJI Hideaki Signed-off-by: David S. Miller --- net/ipv6/ip6_input.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index 4ac5bf30e16a..5b10414e619e 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -118,6 +118,15 @@ int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt ipv6_addr_loopback(&hdr->daddr)) 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 + * must be silently dropped. + */ + if (ipv6_addr_is_multicast(&hdr->daddr) && + IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 0) + goto err; + /* * RFC4291 2.7 * Multicast addresses must not be used as source addresses in IPv6 -- 2.20.1