--filter-track-skb can track skbs re-built from veth_convert_skb_to_xdp_buff #391
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…dp_buff
When XDP is attached to a veth, skbs will be consumed and re-created on
that veth. This is done in the function veth_convert_skb_to_xdp_buff():
```
// drivers/net/veth.c
static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq,
struct xdp_buff *xdp,
struct sk_buff **pskb)
{
struct sk_buff *skb = *pskb;
[...]
nskb = build_skb(page_address(page), PAGE_SIZE);
[...]
skb_copy_header(nskb, skb);
[...]
consume_skb(skb);
skb = nskb;
[...]
}
```
This causes problems for pwru --filter-track-skb because of the new skb
addresses. I ran into a lot of situations where I lost track of NAT-ed
traffic at veth when cilium kind cluster is created by "kind.sh --xdp".
This patch allows pwru to keep track of the new skbs at XDP-attached
veth devices.
Signed-off-by: gray <gray.liang@isovalent.com>
jschwinger233
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When XDP is attached to a veth, skbs will be consumed and re-created on that veth. This is done in the function veth_convert_skb_to_xdp_buff():
This causes problems for pwru --filter-track-skb because of the new skb addresses. I ran into a lot of situations where I lost track of NAT-ed traffic at veth when cilium kind cluster is created by "kind.sh --xdp".
This patch allows pwru to keep track of the new skbs at XDP-attached veth devices.