2007-05-21 19:46:55

by Chris Wright

[permalink] [raw]
Subject: [patch 47/69] IPV6: Send ICMPv6 error on scope violations.

-stable review patch. If anyone has any objections, please let us know.
---------------------

From: David L Stevens <[email protected]>

When an IPv6 router is forwarding a packet with a link-local scope source
address off-link, RFC 4007 requires it to send an ICMPv6 destination
unreachable with code 2 ("not neighbor"), but Linux doesn't. Fix below.

Signed-off-by: David L Stevens <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Chris Wright <[email protected]>

---
net/ipv6/ip6_output.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

--- linux-2.6.21.1.orig/net/ipv6/ip6_output.c
+++ linux-2.6.21.1/net/ipv6/ip6_output.c
@@ -449,10 +449,17 @@ int ip6_forward(struct sk_buff *skb)
*/
if (xrlim_allow(dst, 1*HZ))
ndisc_send_redirect(skb, n, target);
- } else if (ipv6_addr_type(&hdr->saddr)&(IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK
- |IPV6_ADDR_LINKLOCAL)) {
+ } else {
+ int addrtype = ipv6_addr_type(&hdr->saddr);
+
/* This check is security critical. */
- goto error;
+ if (addrtype & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK))
+ goto error;
+ if (addrtype & IPV6_ADDR_LINKLOCAL) {
+ icmpv6_send(skb, ICMPV6_DEST_UNREACH,
+ ICMPV6_NOT_NEIGHBOUR, 0, skb->dev);
+ goto error;
+ }
}

if (skb->len > dst_mtu(dst)) {

--