| Message ID | 20190427131433.4082-1-ssuryaextr@gmail.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net,v3] vrf: Use orig netdev to count Ip6InNoRoutes and a fresh route lookup when sending dest unreach | expand |
On 4/27/19 7:14 AM, Stephen Suryaputra wrote: > When there is no route to an IPv6 dest addr, skb_dst(skb) points > to loopback dev in the case of that the IP6CB(skb)->iif is > enslaved to a vrf. This causes Ip6InNoRoutes to be incremented on the > loopback dev. This also causes the lookup to fail on icmpv6_send() and > the dest unreachable to not sent and Ip6OutNoRoutes gets incremented on > the loopback dev. > > To reproduce: > * Gateway configuration: > ip link add dev vrf_258 type vrf table 258 > ip link set dev enp0s9 master vrf_258 > ip addr add 66:1/64 dev enp0s9 > ip -6 route add unreachable default metric 8192 table 258 > sysctl -w net.ipv6.conf.all.forwarding=1 > sysctl -w net.ipv6.conf.enp0s9.forwarding=1 > * Sender configuration: > ip addr add 66::2/64 dev enp0s9 > ip -6 route add default via 66::1 > and ping 67::1 for example from the sender. > > Fix this by counting on the original netdev and reset the skb dst to > force a fresh lookup. > > v2: Fix typo of destination address in the repro steps. > v3: Simplify the loopback check (per David Ahern) and use reverse > Christmas tree format (per David Miller). > > Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> > Reviewed-by: David Ahern <dsahern@gmail.com> > Tested-by: David Ahern <dsahern@gmail.com> > --- > net/ipv6/route.c | 23 +++++++++++++++++------ > 1 file changed, 17 insertions(+), 6 deletions(-) > Reviewed-by: David Ahern <dsahern@gmail.com>
From: Stephen Suryaputra <ssuryaextr@gmail.com> Date: Sat, 27 Apr 2019 09:14:33 -0400 > When there is no route to an IPv6 dest addr, skb_dst(skb) points > to loopback dev in the case of that the IP6CB(skb)->iif is > enslaved to a vrf. This causes Ip6InNoRoutes to be incremented on the > loopback dev. This also causes the lookup to fail on icmpv6_send() and > the dest unreachable to not sent and Ip6OutNoRoutes gets incremented on > the loopback dev. ... > Fix this by counting on the original netdev and reset the skb dst to > force a fresh lookup. > > v2: Fix typo of destination address in the repro steps. > v3: Simplify the loopback check (per David Ahern) and use reverse > Christmas tree format (per David Miller). > > Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> > Reviewed-by: David Ahern <dsahern@gmail.com> > Tested-by: David Ahern <dsahern@gmail.com> Applied, thanks.
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 7178e32eb15d..b4899f0de0d0 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3668,23 +3668,34 @@ int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg) static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes) { - int type; struct dst_entry *dst = skb_dst(skb); + struct net *net = dev_net(dst->dev); + struct inet6_dev *idev; + int type; + + if (netif_is_l3_master(skb->dev) && + dst->dev == net->loopback_dev) + idev = __in6_dev_get_safely(dev_get_by_index_rcu(net, IP6CB(skb)->iif)); + else + idev = ip6_dst_idev(dst); + switch (ipstats_mib_noroutes) { case IPSTATS_MIB_INNOROUTES: type = ipv6_addr_type(&ipv6_hdr(skb)->daddr); if (type == IPV6_ADDR_ANY) { - IP6_INC_STATS(dev_net(dst->dev), - __in6_dev_get_safely(skb->dev), - IPSTATS_MIB_INADDRERRORS); + IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS); break; } /* FALLTHROUGH */ case IPSTATS_MIB_OUTNOROUTES: - IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst), - ipstats_mib_noroutes); + IP6_INC_STATS(net, idev, ipstats_mib_noroutes); break; } + + /* Start over by dropping the dst for l3mdev case */ + if (netif_is_l3_master(skb->dev)) + skb_dst_drop(skb); + icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0); kfree_skb(skb); return 0;
When there is no route to an IPv6 dest addr, skb_dst(skb) points to loopback dev in the case of that the IP6CB(skb)->iif is enslaved to a vrf. This causes Ip6InNoRoutes to be incremented on the loopback dev. This also causes the lookup to fail on icmpv6_send() and the dest unreachable to not sent and Ip6OutNoRoutes gets incremented on the loopback dev. To reproduce: * Gateway configuration: ip link add dev vrf_258 type vrf table 258 ip link set dev enp0s9 master vrf_258 ip addr add 66:1/64 dev enp0s9 ip -6 route add unreachable default metric 8192 table 258 sysctl -w net.ipv6.conf.all.forwarding=1 sysctl -w net.ipv6.conf.enp0s9.forwarding=1 * Sender configuration: ip addr add 66::2/64 dev enp0s9 ip -6 route add default via 66::1 and ping 67::1 for example from the sender. Fix this by counting on the original netdev and reset the skb dst to force a fresh lookup. v2: Fix typo of destination address in the repro steps. v3: Simplify the loopback check (per David Ahern) and use reverse Christmas tree format (per David Miller). Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Tested-by: David Ahern <dsahern@gmail.com> --- net/ipv6/route.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-)