[ovs-dev] [PATCH ovn] northd: set packet length in check_pkt_larger()

Gabriele Cerami gcerami at redhat.com
Thu Jun 18 08:46:52 UTC 2020

On 17 Jun, Lorenzo Bianconi wrote:
> > What would be the case if there is a VLAN tag set ?
> I am not expert about how ovs manages vlan tags, but looking at [1] and [2], it seems
> to me vlan header is not accounted in skb->len
> Regards,
> Lorenzo
> [1] https://github.com/torvalds/linux/blob/master/net/core/dev.c#L5117
> [2] https://github.com/torvalds/linux/blob/master/net/openvswitch/vport-netdev.c#L29

I don't have the full picture of what happens either, but it would seem
the vlan header is accounted

>From here:
skb_push resizes the skb adding VLAN_HLEN bytes, modifying skb->len

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