On Fri, Apr 29, 2016 at 3:28 PM, Jarno Rajahalme <ja...@ovn.org> wrote: > UDP tunnel segmentation code relies on the inner offsets being set for > an UDP tunnel GSO packet. The inner *_complete() functions will set > the inner offsets only if the encapsulation is set before calling > them, but udp_gro_complete() set it only after the inner *_complete() > functions were done. > > Also, remove the setting of the inner_mac_header in udp_gro_complete() > as it was wrongly set to the beginning of the UDP tunnel header rather > than the inner MAC header. > How did you test this? Do you have a test case for the problem?
The general problem is that skb->encapsulation is the indicator that the inner offsets are valid, but there are many instances where we set skb->encapsulation independently of setting the inner headers. It would be nice if setting the flag and setting the inner headers were somehow unified. Thanks, Tom > Signed-off-by: Jarno Rajahalme <ja...@ovn.org> > --- > net/ipv4/udp_offload.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c > index 0ed2daf..e330c0e 100644 > --- a/net/ipv4/udp_offload.c > +++ b/net/ipv4/udp_offload.c > @@ -399,6 +399,11 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff) > > uh->len = newlen; > > + /* Set encapsulation before calling into inner gro_complete() > functions > + * to make them set up the inner offsets. > + */ > + skb->encapsulation = 1; > + > rcu_read_lock(); > > uo_priv = rcu_dereference(udp_offload_base); > @@ -421,9 +426,6 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff) > if (skb->remcsum_offload) > skb_shinfo(skb)->gso_type |= SKB_GSO_TUNNEL_REMCSUM; > > - skb->encapsulation = 1; > - skb_set_inner_mac_header(skb, nhoff + sizeof(struct udphdr)); > - > return err; > } > > -- > 2.7.4 >
