fixing coverity found defects - memory corruption, null dereference

(cherry picked from commit fd57609)
(cherry picked from commit 56a7230)

modules/enum/enum.c

@@ -400,6 +400,12 @@ int is_from_user_enum_2(struct sip_msg* _msg, char* _suffix, char* _service)
 			proto = PROTO_NONE;
 			he = sip_resolvehost(&luri.host, &zp, &proto,
 				(luri.type==SIPS_URI_T)?1:0 , 0);
+			if (he == NULL){
+				LM_ERR("Resolving URI <%.*s> failed\n",
+					   result.len, result.s);
+				free_rdata_list(head); /*clean up*/
+				return -9;
+			}
 
 			hostent2ip_addr(&addr, he, 0);
 

modules/permissions/rule.c

@@ -128,6 +128,11 @@ expression *new_expression(char *str)
 		return 0;
 	}
 
+	if (strlen(str) > EXPRESSION_LENGTH){
+		LM_ERR("expresion too long\n");
+		pkg_free(e);
+		return 0;
+	}
 	strcpy(e->value, str);
 
 	e->reg_value = (regex_t*)pkg_malloc(sizeof(regex_t));