On Fri, Oct 27, 2017 at 09:45:34AM -0700, John Fastabend wrote: > SK_SKB program types use bpf_compute_data to store the end of the > packet data. However, bpf_compute_data assumes the cb is stored in the > qdisc layer format. But, for SK_SKB this is the wrong layer of the > stack for this type. > > It happens to work (sort of!) because in most cases nothing happens > to be overwritten today. This is very fragile and error prone. > Fortunately, we have another hole in tcp_skb_cb we can use so lets > put the data_end value there. > > Note, SK_SKB program types do not use data_meta, they are failed by > sk_skb_is_valid_access(). > > Signed-off-by: John Fastabend <john.fastab...@gmail.com>
Acked-by: Alexei Starovoitov <a...@kernel.org>
