Merge branch 'net-fail-route'
David Ahern says:
====================
net: Fail route add with unsupported nexthop attribute
RTA_VIA was added for MPLS as a way of specifying a gateway from a
different address family. IPv4 and IPv6 do not currently support RTA_VIA
so using it leads to routes that are not what the user intended. Catch
and fail - returning a proper error message.
MPLS on the other hand does not support RTA_GATEWAY since it does not
make sense to have a nexthop from the MPLS address family. Similarly,
catch and fail - returning a proper error message.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index fe4f6a6..ed14ec2 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -710,6 +710,10 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
case RTA_GATEWAY:
cfg->fc_gw = nla_get_be32(attr);
break;
+ case RTA_VIA:
+ NL_SET_ERR_MSG(extack, "IPv4 does not support RTA_VIA attribute");
+ err = -EINVAL;
+ goto errout;
case RTA_PRIORITY:
cfg->fc_priority = nla_get_u32(attr);
break;
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ce15dc4..b7a6200 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;
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 7d55d4c0..fa763e2 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -1838,6 +1838,9 @@ static int rtm_to_route_config(struct sk_buff *skb,
goto errout;
break;
}
+ case RTA_GATEWAY:
+ NL_SET_ERR_MSG(extack, "MPLS does not support RTA_GATEWAY attribute");
+ goto errout;
case RTA_VIA:
{
if (nla_get_via(nla, &cfg->rc_via_alen,
