net/sched: act_vlan: No dump for unset priority

Dump vlan priority only if it has been previously set.

Fix the tests accordingly.

Signed-off-by: Boris Sukholitko <boris.sukholitko@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/act_vlan.c b/net/sched/act_vlan.c
index a108469..71f2015 100644
--- a/net/sched/act_vlan.c
+++ b/net/sched/act_vlan.c
@@ -307,8 +307,8 @@ static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
 	    (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) ||
 	     nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
 			  p->tcfv_push_proto) ||
-	     (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY,
-					      p->tcfv_push_prio))))
+	     (p->tcfv_push_prio_exists &&
+	      nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY, p->tcfv_push_prio))))
 		goto nla_put_failure;
 
 	if (p->tcfv_action == TCA_VLAN_ACT_PUSH_ETH) {