From e3818541b49fb88650ba339d33cc53e4095da5b3 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Tue, 26 Feb 2019 09:00:03 -0800 Subject: ipv6: Return error for RTA_VIA attribute IPv6 currently does not support nexthops outside of the AF_INET6 family. Specifically, it does not handle RTA_VIA attribute. If it is passed in a route add request, the actual route added only uses the device which is clearly not what the user intended: $ ip -6 ro add 2001:db8:2::/64 via inet 172.16.1.1 dev eth0 $ ip ro ls ... 2001:db8:2::/64 dev eth0 metric 1024 pref medium Catch this and fail the route add: $ ip -6 ro add 2001:db8:2::/64 via inet 172.16.1.1 dev eth0 Error: IPv6 does not support RTA_VIA attribute. Fixes: 03c0566542f4c ("mpls: Netlink commands to add, remove, and dump routes") Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/ipv6/route.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/ipv6') diff --git a/net/ipv6/route.c b/net/ipv6/route.c index ce15dc4ccbfa..b7a620023a52 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -4182,6 +4182,10 @@ static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]); cfg->fc_flags |= RTF_GATEWAY; } + if (tb[RTA_VIA]) { + NL_SET_ERR_MSG(extack, "IPv6 does not support RTA_VIA attribute"); + goto errout; + } if (tb[RTA_DST]) { int plen = (rtm->rtm_dst_len + 7) >> 3; -- cgit v1.2.3