Commit 9f56220f authored Oct 24, 2011 by Andreas Hofmeister Committed by David S. Miller Oct 24, 2011

ipv6: Do not use routes from locally generated RAs



When hybrid mode is enabled (accept_ra == 2), the kernel also sees RAs
generated locally. This is useful since it allows the kernel to auto-configure
its own interface addresses.

However, if 'accept_ra_defrtr' and/or 'accept_ra_rtr_pref' are set and the
locally generated RAs announce the default route and/or other route information,
the kernel happily inserts bogus routes with its own address as gateway.

With this patch, adding routes from an RA will be skiped when the RAs source
address matches any local address, just as if 'accept_ra_defrtr' and
'accept_ra_rtr_pref' were set to 0.

Signed-off-by: Andreas Hofmeister <andi@collax.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 48855432

net/ipv6/ndisc.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -1221,6 +1221,9 @@ static void ndisc_router_discovery(struct sk_buff *skb)
		if (!in6_dev->cnf.accept_ra_defrtr)
		goto skip_defrtr;

		if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0))
		goto skip_defrtr;

		lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);

		#ifdef CONFIG_IPV6_ROUTER_PREF
		@@ -1343,6 +1346,9 @@ static void ndisc_router_discovery(struct sk_buff *skb)
		goto out;

		#ifdef CONFIG_IPV6_ROUTE_INFO
		if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0))
		goto skip_routeinfo;

		if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
		struct nd_opt_hdr *p;
		for (p = ndopts.nd_opts_ri;
		@@ -1360,6 +1366,8 @@ static void ndisc_router_discovery(struct sk_buff *skb)
		&ipv6_hdr(skb)->saddr);
		}
		}

		skip_routeinfo:
		#endif

		#ifdef CONFIG_IPV6_NDISC_NODETYPE