From: Eric Dumazet <eduma...@google.com>
Date: Tue, 6 Nov 2018 14:25:52 -0800
> + if (unlikely(nlen > sizeof(struct ipv6hdr))) {
> + if (memcmp(iph + 1, iph2 + 1,
> + nlen - sizeof(struct ipv6hdr)))
> + goto not_same_flow;
> + }
Is this even possible?
off = skb_gro_offset(skb);
hlen = off + sizeof(*iph);
iph = skb_gro_header_fast(skb, off);
off is some offset to the ipv6hdr in skb. This is GRO's CB data_offset.
skb_set_network_header(skb, off);
skb_gro_pull(skb, sizeof(*iph));
skb_set_transport_header(skb, skb_gro_offset(skb));
Set network header to location of iph in SKB.
GRO pull causes an incremebt of data_offset by sizeof(*iph) bytes.
Set transport header to new data_offset value.
nlen = skb_network_header_len(skb);
This is transport_header - network_header.
>From what I can see, it is impossible for this to take on any value
other than sizeof(*ipv6hdr).
If you agree, please let's get rid of nlen and this useless code, and
replace with sizeof(*ipv6hdr) as needed.
Thanks.
