fix for bug#14089 FROM list subquery always fails when

                  information_schema is current database
  skip the check of I_S tables if table is derived table

mysql-test/r/information_schema.result

@@ -1013,3 +1013,15 @@ grant all on information_schema.* to 'user1'@'localhost';
 ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
 grant select on information_schema.* to 'user1'@'localhost';
 ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
+use test;
+create table t1(id int);
+insert into t1(id) values (1);
+select 1 from (select 1 from test.t1) a;
+1
+1
+use information_schema;
+select 1 from (select 1 from test.t1) a;
+1
+1
+use test;
+drop table t1;

mysql-test/t/information_schema.test

@@ -715,3 +715,15 @@ select  ROUTINE_NAME from routines;
 grant all on information_schema.* to 'user1'@'localhost';
 --error 1044
 grant select on information_schema.* to 'user1'@'localhost';
+
+#
+# Bug#14089 FROM list subquery always fails when information_schema is current database
+#
+use test;
+create table t1(id int);
+insert into t1(id) values (1);
+select 1 from (select 1 from test.t1) a;
+use information_schema;
+select 1 from (select 1 from test.t1) a;
+use test;
+drop table t1;

sql/sql_parse.cc

@@ -6197,7 +6197,7 @@ TABLE_LIST *st_select_lex::add_table_to_list(THD *thd,
   ptr->force_index= test(table_options & TL_OPTION_FORCE_INDEX);
   ptr->ignore_leaves= test(table_options & TL_OPTION_IGNORE_LEAVES);
   ptr->derived=	    table->sel;
-  if (!my_strcasecmp(system_charset_info, ptr->db,
+  if (!ptr->derived && !my_strcasecmp(system_charset_info, ptr->db,
                                       information_schema_name.str))
   {
     ST_SCHEMA_TABLE *schema_table= find_schema_table(thd, ptr->table_name);