On 11/29/23 10:47 PM, Florian Westphal wrote:
D. Wythe <alibuda@xxxxxxxxxxxxxxxxx> wrote:
And my origin intention was to allow ebpf progs to return NF_STOLEN, we are
trying to modify some netfilter modules via ebpf,
and some scenarios require the use of NF_STOLEN, but from your description,
NF_STOLEN can only be supported via a trusted helper, as least as far as
I understand.
Otherwise verifier would have to guarantee that any branch that returns
NF_STOLEN has released the skb, or passed it to a function that will
release the skb in the near future.
Thank you very much for your help. I now understand the difficulty here.
The verifier cannot determine whether the consume_skb() was executed or not,
when the return value goes to NF_STOLEN.
We may use NF_DROP at first, it won't be make much difference for us now.
Also, do you have any plans to support this helper?
Best wishes,
D. Wythe
