| Message ID | 1491188266363.26046@alliedtelesis.co.nz |
|---|---|
| State | Awaiting Upstream, archived |
| Delegated to: | David Miller |
| Headers | show |
On 4/2/17 10:57 PM, Jack Ma wrote: > diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c > index c0cc6aa..07168d4 100644 > --- a/net/ipv4/netfilter.c > +++ b/net/ipv4/netfilter.c > @@ -46,6 +46,14 @@ int ip_route_me_harder(struct net *net, struct sk_buff *skb, unsigned int addr_t > fl4.flowi4_oif = l3mdev_master_ifindex(dev); How does the above line (which is part of this block: fl4.flowi4_oif = sk ? sk->sk_bound_dev_if : 0; if (!fl4.flowi4_oif) fl4.flowi4_oif = l3mdev_master_ifindex(dev); ) not work? The dst should be set on the skb at this point and the device would reference the VRF. > fl4.flowi4_mark = skb->mark; > fl4.flowi4_flags = flags; > + > + /* Since we have already known this is vrf flow passed by > + * mangle table, we wrap the oif with the master interface. > + */ > + if (fl4.flowi4_oif == 0 && fl4.daddr && skb->dev && > + netif_index_is_l3_master(net, skb->dev->ifindex)) > + fl4.flowi4_oif = skb->dev->ifindex; > + > rt = ip_route_output_key(net, &fl4); > if (IS_ERR(rt)) > return PTR_ERR(rt); >
0001-Wrap-vrf-traffic-passed-by-mangle-table-with-correct.patch
Hi David, I formatted a patch to support vrf flow passed by iptables(mangle table). And previously, we lost the flow.oif which would result in a routing look-up failure. This patch wraps vrf response flow with the correct master interface by using the skb->dev, which was set to the real ingress device. Without this patch, VRF traffic permitted by firewall rules that changes nf_mark would be dropped while doing fib_lookup. Kernel documentations suggested two way of fixing this: < [2] Iptables on ingress supports PREROUTING with skb->dev set to the real ingress device and both INPUT and PREROUTING rules with skb->dev set to the VRF device. For egress POSTROUTING and OUTPUT rules can be written using either the VRF device or real egress device. > Could you please look at this patch and give me some feedback? Thanks for your time and considerations. Regards, Jack