On Sun, Nov 11, 2018 at 12:43:27AM +0100, Nicolas Dichtel wrote:
> Le 09/11/2018 à 19:51, Martin Lau a écrit :
> > On Thu, Nov 08, 2018 at 04:11:37PM +0100, Nicolas Dichtel wrote:
> [snip]
> >> +static int bpf_skb_data_shrink(struct sk_buff *skb, u32 len)
> >> +{
> >> + unsigned short hhlen = skb->dev->header_ops ?
> >> + skb->dev->hard_header_len : 0;
> >> + int ret;
> >> +
> >> + ret = skb_unclone(skb, GFP_ATOMIC);
> >> + if (unlikely(ret < 0))
> >> + return ret;
> >> +
> >> + __skb_pull(skb, len);
> >> + skb_reset_mac_header(skb);
> >> + skb_reset_network_header(skb);
> >> + skb->network_header += hhlen;
Nit. skb_set_network_header(skb, hhlen);
Othen than that
Acked-by: Martin KaFai Lau <ka...@fb.com>
> >> + skb_reset_transport_header(skb);
> > hmm...why transport_header does not need += hhlen here
> > while network_header does?
>
> network_header is mandatory because bpf_redirect(BPF_F_INGRESS) can be called
> and network_header is expected to be correctly set in this case.
> For transport_header, I choose to not set it, because the stack will set it
> later (for example ip_rcv_core()).
ic. make sense.
