bonding: don't add duplicate targets to arp_ip_target

Print a warning and skip them.
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -4588,7 +4588,11 @@ static int bond_check_params(struct bond_params *params)
 				   arp_ip_target[i]);
 			arp_interval = 0;
 		} else {
+			if (bond_get_targets_ip(arp_target, ip) == -1)
 				arp_target[arp_ip_count++] = ip;
+			else
+				pr_warning("Warning: duplicate address %pI4 in arp_ip_target, skipping\n",
+					   &ip);
 		}
 	}