netdev-offload-tc: Use nl_msg_put_flag for OVS_TUNNEL_KEY_ATTR_CSUM.

When a tunnel port gets added to the bridge setting the checksum option
to true:

  ovs-vsctl add-port br0 geneve0         \
    -- set interface geneve0 type=geneve \
    options:remote_ip=<remote_ip> options:key=<key> options:csum=true

the flow dump for the outgoing traffic will include a
"bad key length 1 ..." message:

  ovs-appctl dpctl/dump-flows --names -m
  ufid:<>, ..., dp:tc,
  actions:set(tunnel(tun_id=<>,dst=<>,ttl=64,tp_dst=6081,
                     key6(bad key length 1, expected 0)(01)flags(key)))
          ,genev_sys_6081

This is due to a mismatch present between the expected length (zero
for OVS_TUNNEL_KEY_ATTR_CSUM in ovs_tun_key_attr_lens) and the
current one.

With this patch the same flow dump becomes:

  ovs-appctl dpctl/dump-flows --names -m
  ufid:<>, ..., dp:tc,
  actions:set(tunnel(tun_id=<>,dst=<>,ttl=64,tp_dst=6081,
                     flags(csum|key))),genev_sys_6081

Fixes: d9677a1f0eaf ("netdev-tc-offloads: TC csum option is not matched with tunnel configuration")
Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: Paolo Valerio <pvalerio@redhat.com>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

1 files changed, 1 insertions, 2 deletions

diff --git a/lib/netdev-offload-tc.c b/lib/netdev-offload-tc.c
index b8fd1d82f..68c4c7ebd 100644
--- a/lib/netdev-offload-tc.c
+++ b/lib/netdev-offload-tc.c
@@ -689,8 +689,7 @@ parse_tc_flower_to_match(struct tc_flower *flower,
                                     action->encap.tp_dst);
                 }
                 if (!action->encap.no_csum) {
-                    nl_msg_put_u8(buf, OVS_TUNNEL_KEY_ATTR_CSUM,
-                                  !action->encap.no_csum);
+                    nl_msg_put_flag(buf, OVS_TUNNEL_KEY_ATTR_CSUM);
                 }
 
                 parse_tc_flower_geneve_opts(action, buf);