Re: [PATCH bpf-next v2 4/4] bpf: more lenient bpf_skb_net_shrink() with BPF_F_ADJ_ROOM_FIXED_GSO

From: Daniel Borkmann
Date: Thu Jun 24 2021 - 10:05:44 EST


On 6/17/21 2:09 AM, Maciej Żenczykowski wrote:
From: Maciej Żenczykowski <maze@xxxxxxxxxx>

This is to more closely match behaviour of bpf_skb_change_proto()
which now does not adjust gso_size, and thus thoretically supports
all gso types, and does not need to set SKB_GSO_DODGY nor reset
gso_segs to zero.

Something similar should probably be done with bpf_skb_net_grow(),
but that code scares me.

Took in all except this one, would be good to have a complete solution for
both bpf_skb_net_{shrink,grow}(). If you don't have the cycles, I'll look
into it.

Thanks,
Daniel