[IPV4] IPVS: sanity check of threshold setting and code tidy up

net/ipv4/ipvs/Kconfig

@@ -11,7 +11,7 @@ config	IP_VS
 	  IP Virtual Server support will let you build a high-performance
 	  virtual server based on cluster of two or more real servers. This
 	  option must be enabled for at least one of the clustered computers
-	  that will take care of intercepting incomming connections to a
+	  that will take care of intercepting incoming connections to a
 	  single IP address and scheduling them to real servers.
 
 	  Three request dispatching techniques are implemented, they are

net/ipv4/ipvs/ip_vs_ctl.c

@@ -790,6 +790,12 @@ ip_vs_add_dest(struct ip_vs_service *svc, struct ip_vs_dest_user *udest)
 		return -ERANGE;
 	}
 
+	if (udest->l_threshold > udest->u_threshold) {
+		IP_VS_ERR("ip_vs_add_dest(): lower threshold is higher than "
+			  "upper threshold\n");
+		return -ERANGE;
+	}
+
 	/*
 	 * Check if the dest already exists in the list
 	 */
@@ -885,7 +891,13 @@ ip_vs_edit_dest(struct ip_vs_service *svc, struct ip_vs_dest_user *udest)
 	EnterFunction(2);
 
 	if (udest->weight < 0) {
-		IP_VS_ERR("ip_vs_add_dest(): server weight less than zero\n");
+		IP_VS_ERR("ip_vs_edit_dest(): server weight less than zero\n");
+		return -ERANGE;
+	}
+
+	if (udest->l_threshold > udest->u_threshold) {
+		IP_VS_ERR("ip_vs_edit_dest(): lower threshold is higher than "
+			  "upper threshold\n");
 		return -ERANGE;
 	}