4.20-stable review patch. If anyone has any objections, please let me know.
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From: David Ahern dsahern@gmail.com
[ Upstream commit e3818541b49fb88650ba339d33cc53e4095da5b3 ]
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 dsahern@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv6/route.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -4163,6 +4163,10 @@ static int rtm_to_fib6_config(struct sk_ 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;