openvswitch: Reset key metadata for packet execution.

Userspace packet execute command pass down flow key for given
packet. But userspace can skip some parameter with zero value.
Therefore kernel needs to initialize key metadata to zero.

Fixes: 0714812134 ("openvswitch: Eliminate memset() from flow_extract.")
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c
index e2c348b..50ec42f 100644
--- a/net/openvswitch/flow.c
+++ b/net/openvswitch/flow.c
@@ -717,6 +717,8 @@
 {
 	int err;
 
+	memset(key, 0, OVS_SW_FLOW_KEY_METADATA_SIZE);
+
 	/* Extract metadata from netlink attributes. */
 	err = ovs_nla_get_flow_metadata(attr, key, log);
 	if (err)