selftests: udp gso with corking

Corked sockets take a different path to construct a udp datagram than
the lockless fast path. Test this alternate path.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/udpgso.sh

@@ -21,3 +21,9 @@ echo "ipv4 connected"
 # blocked on 2nd loopback address
 # echo "ipv6 connected"
 # ./in_netns.sh ./udpgso -6 -c
+
+echo "ipv4 msg_more"
+./in_netns.sh ./udpgso -4 -C -m
+
+echo "ipv6 msg_more"
+./in_netns.sh ./udpgso -6 -C -m