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> > /* icmpv6_echo_reply, net/ipv6/icmp.c:923 */ > struct net *net = dev_net_rcu(skb->dev); > > Under a VRF, skb->dev is the VRF master device, so dev_net_rcu(skb->dev) > returns the netns of the master rather than the netns the packet is > destined to. The route lookup for the unreach and the send policy for > the echo reply (ratelimit, IPsec, route) then run against the wrong > namespace. The rt6_lookup may miss the route to the source, leaving > skb2->dev unset, and the echo reply is emitted/routed per the ingress > netns instead of the destination netns. > > The IPv4 ICMP echo path already uses the destination netns via > skb_dst_dev_net_rcu(skb) (net/ipv4/icmp.c:1123 and :1267), and the IPv6 > echo path still uses dev_net_rcu(skb->dev). > > Use skb_dst_dev_net_rcu(skb) at both IPv6 sites so the namespace is > taken from the skb destination, matching the IPv4 path. I don't understand any of this. VRF master and slave are always in the same netns. Same comment about the IPv4 patch.