openvswitch: Fixed nd target mask field in the flow dump.

IPv6 nd target mask was not getting populated in flow dump.

In the function __ovs_nla_put_key the icmp code mask field was checked
instead of icmp code key field to classify the flow as neighbour discovery.

ufid:bdfbe3e5-60c2-43b0-a5ff-dfcac1c37328, recirc_id(0),dp_hash(0/0),
skb_priority(0/0),in_port(ovs-nm1),skb_mark(0/0),ct_state(0/0),
ct_zone(0/0),ct_mark(0/0),ct_label(0/0),
eth(src=00:00:00:00:00:00/00:00:00:00:00:00,
dst=00:00:00:00:00:00/00:00:00:00:00:00),
eth_type(0x86dd),
ipv6(src=::/::,dst=::/::,label=0/0,proto=58,tclass=0/0,hlimit=0/0,frag=no),
icmpv6(type=135,code=0),
nd(target=2001::2/::,
sll=00:00:00:00:00:00/00:00:00:00:00:00,
tll=00:00:00:00:00:00/00:00:00:00:00:00),
packets:10, bytes:860, used:0.504s, dp:ovs, actions:ovs-nm2

Fixes: e644571 (openvswitch: Restructure datapath.c and flow.c)
Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Link: https://lore.kernel.org/r/20220328054148.3057-1-martinvarghesenokia@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: Martin Varghese

net/openvswitch/flow_netlink.c

@@ -2230,8 +2230,8 @@ static int __ovs_nla_put_key(const struct sw_flow_key *swkey,
 			icmpv6_key->icmpv6_type = ntohs(output->tp.src);
 			icmpv6_key->icmpv6_code = ntohs(output->tp.dst);
 
-			if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
-			    icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
+			if (swkey->tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
+			    swkey->tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 				struct ovs_key_nd *nd_key;
 
 				nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));