dpif-netlink: For non-Ethernet, use Ethertype from packet_type.

For non-Ethernet flows, when fixing up the netlink message we need make
sure to pass down a valid Ethertype. The kernel does not understand
packet_type so it's implicitly encoded by the absence of _ETHERNET and
exact match of _ETHERTYPE. Without this change match_validate in the
kernel complains when trying to match packets from L3 tunnels.
e.g.
  openvswitch: netlink: Unexpected mask (mask=110088, allowed=3d9804c)

The mask use to always be set in xlate_wc_init() and xlate_wc_finish(),
but that changed for non-Ethernet frames with the commit listed below.

Fixes: 3d4b2e6eb74e ("userspace: Add OXM field MFF_PACKET_TYPE")
Signed-off-by: Joe Stringer <joe@ovn.org>
Co-authored-by: Eric Garver <e@erig.me>
Acked-by: Eric Garver <e@erig.me>

diff --git a/lib/dpif-netlink.c b/lib/dpif-netlink.c
index 63ef3de5c7d182d54909a0e30cadcf83b0daa046..55effd1f91a8cbdd13694510e441d2e266aa4468 100644 (file)
--- a/lib/dpif-netlink.c
+++ b/lib/dpif-netlink.c
@@ -3434,8 +3434,9 @@ dpif_netlink_flow_from_ofpbuf(struct dpif_netlink_flow *flow,
 
 
 /*
- * If PACKET_TYPE attribute is present in 'data', it filters PACKET_TYPE out,
- * then puts 'data' to 'buf'.
+ * If PACKET_TYPE attribute is present in 'data', it filters PACKET_TYPE out.
+ * If the flow is not Ethernet, the OVS_KEY_ATTR_PACKET_TYPE is converted to
+ * OVS_KEY_ATTR_ETHERTYPE. Puts 'data' to 'buf'.
  */
 static void
 put_exclude_packet_type(struct ofpbuf *buf, uint16_t type,
@@ -3458,6 +3459,20 @@ put_exclude_packet_type(struct ofpbuf *buf, uint16_t type,
         ofs = nl_msg_start_nested(buf, type);
         nl_msg_put(buf, data, first_chunk_size);
         nl_msg_put(buf, next_attr, second_chunk_size);
+        if (!nl_attr_find__(data, data_len, OVS_KEY_ATTR_ETHERNET)) {
+            ovs_be16 pt = pt_ns_type_be(nl_attr_get_be32(packet_type));
+            const struct nlattr *nla;
+
+            nla = nl_attr_find(buf, NLA_HDRLEN, OVS_KEY_ATTR_ETHERTYPE);
+            if (nla) {
+                ovs_be16 *ethertype;
+
+                ethertype = CONST_CAST(ovs_be16 *, nl_attr_get(nla));
+                *ethertype = pt;
+            } else {
+                nl_msg_put_be16(buf, OVS_KEY_ATTR_ETHERTYPE, pt);
+            }
+        }
         nl_msg_end_nested(buf, ofs);
     } else {
         nl_msg_put_unspec(buf, type, data, data_len);