Bug#11765255 - 58201: VALGRIND/CRASH WHEN ORDERING BY MULTIPLE AGGREGATE FUNCTIONS

We must allocate a larger ref_pointer_array. We failed to account for extra
items allocated here:
#0  find_order_in_list 
  uint el= all_fields.elements;
  all_fields.push_front(order_item); /* Add new field to field list. */
  ref_pointer_array[el]= order_item;
  order->item= ref_pointer_array + el;
#1  setup_order
#2  setup_without_group
#3  JOIN::prepare


mysql-test/r/order_by.result:
  New test case.
mysql-test/r/union.result:
  New test case.
mysql-test/t/order_by.test:
  New test case.
mysql-test/t/union.test:
  New test case.
sql/sql_lex.cc:
  find_order_in_list() may need some extra space, so multiply og_num by two.
sql/sql_union.cc:
  For UNION, the 'n_sum_items' are accumulated in the "global_parameters" select_lex.
  This number must be propagated to setup_ref_array()
  
  When preparing a 'fake_select_lex' we need to use global_parameters->order_list
  rather than fake_select_lex->order_list (see comments inside st_select_lex_unit::cleanup)

mysql-test/r/order_by.result

@@ -1664,4 +1664,11 @@ a	1
 3	1
 2	1
 DROP TABLE t1;
+#
+# Bug#11765255 58201:
+# VALGRIND/CRASH WHEN ORDERING BY MULTIPLE AGGREGATE FUNCTIONS
+#
+select 1 order by max(1) + min(1);
+1
+1
 End of 5.1 tests

mysql-test/r/union.result

@@ -1647,4 +1647,61 @@ b
 1
 2
 DROP TABLE t1,t2;
+#
+# Bug#11765255 58201:
+# VALGRIND/CRASH WHEN ORDERING BY MULTIPLE AGGREGATE FUNCTIONS
+#
+select 1 as foo
+union
+select 2
+union
+select 3
+union
+select 4
+order by max(42) + max(1) + max(1) + max(1) + max(1) + max(1)
+;
+foo
+1
+prepare stmt1 from 'select 1 as foo
+union
+select 2
+union
+select 3
+union
+select 4
+order by max(42) + max(1) + max(1) + max(1) + max(1) + max(1)
+';
+execute stmt1;
+foo
+1
+execute stmt1;
+foo
+1
+select 1 as foo
+union
+select 2
+union
+select 3
+union
+(select 4)
+order by max(42) + max(1) + max(1) + max(1) + max(1) + max(1)
+;
+foo
+1
+prepare stmt1 from 'select 1 as foo
+union
+select 2
+union
+select 3
+union
+(select 4)
+order by max(42) + max(1) + max(1) + max(1) + max(1) + max(1)
+';
+execute stmt1;
+foo
+1
+execute stmt1;
+foo
+1
+deallocate prepare stmt1;
 End of 5.1 tests

mysql-test/t/order_by.test

@@ -1508,4 +1508,11 @@ SELECT DISTINCT a,1 FROM t1 WHERE a <> 1 ORDER BY a DESC;
 
 DROP TABLE t1;
 
+--echo #
+--echo # Bug#11765255 58201:
+--echo # VALGRIND/CRASH WHEN ORDERING BY MULTIPLE AGGREGATE FUNCTIONS
+--echo #
+
+select 1 order by max(1) + min(1);
+
 --echo End of 5.1 tests

mysql-test/t/union.test

@@ -1156,4 +1156,45 @@ SELECT * FROM t2 UNION SELECT * FROM t2
 DROP TABLE t1,t2;
 
 
+--echo #
+--echo # Bug#11765255 58201:
+--echo # VALGRIND/CRASH WHEN ORDERING BY MULTIPLE AGGREGATE FUNCTIONS
+--echo #
+
+let $my_stmt=
+select 1 as foo
+union
+select 2
+union
+select 3
+union
+select 4
+order by max(42) + max(1) + max(1) + max(1) + max(1) + max(1)
+;
+
+eval $my_stmt;
+
+eval prepare stmt1 from '$my_stmt';
+execute stmt1;
+execute stmt1;
+
+let $my_stmt=
+select 1 as foo
+union
+select 2
+union
+select 3
+union
+(select 4)
+order by max(42) + max(1) + max(1) + max(1) + max(1) + max(1)
+;
+
+eval $my_stmt;
+
+eval prepare stmt1 from '$my_stmt';
+execute stmt1;
+execute stmt1;
+
+deallocate prepare stmt1;
+
 --echo End of 5.1 tests

sql/sql_lex.cc

@@ -1987,6 +1987,9 @@ bool st_select_lex::setup_ref_array(THD *thd, uint order_group_num)
   if (ref_pointer_array)
     return 0;
 
+  // find_order_in_list() may need some extra space, so multiply by two.
+  order_group_num*= 2;
+
   /*
     We have to create array in prepared statement memory if it is
     prepared statement

sql/sql_union.cc

-/*
-   Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -403,15 +402,27 @@ bool st_select_lex_unit::prepare(THD *thd_arg, select_result *sel_result,
 	  fake_select_lex->table_list.empty();
 	  DBUG_RETURN(TRUE);
 	}
+
+        /*
+          Fake st_select_lex should have item list for correct ref_array
+          allocation.
+        */
 	fake_select_lex->item_list= item_list;
 
 	thd_arg->lex->current_select= fake_select_lex;
+
+        /*
+          We need to add up n_sum_items in order to make the correct
+          allocation in setup_ref_array().
+        */
+        fake_select_lex->n_child_sum_items+= global_parameters->n_sum_items;
+
 	saved_error= fake_select_lex->join->
 	  prepare(&fake_select_lex->ref_pointer_array,
 		  fake_select_lex->table_list.first,
 		  0, 0,
-		  fake_select_lex->order_list.elements,
-		  fake_select_lex->order_list.first,
+                  global_parameters->order_list.elements, // og_num
+                  global_parameters->order_list.first,    // order
 		  NULL, NULL, NULL,
 		  fake_select_lex, this);
 	fake_select_lex->table_list.empty();
@@ -579,11 +590,21 @@ bool st_select_lex_unit::exec()
 	}
         fake_select_lex->join->no_const_tables= TRUE;
 
-	/*
-	  Fake st_select_lex should have item list for correctref_array
-	  allocation.
-	*/
-	fake_select_lex->item_list= item_list;
+        /*
+          Fake st_select_lex should have item list for correct ref_array
+          allocation.
+        */
+        fake_select_lex->item_list= item_list;
+
+        /*
+          We need to add up n_sum_items in order to make the correct
+          allocation in setup_ref_array().
+          Don't add more sum_items if we have already done JOIN::prepare
+          for this (with a different join object)
+        */
+        if (!fake_select_lex->ref_pointer_array)
+          fake_select_lex->n_child_sum_items+= global_parameters->n_sum_items;
+
         saved_error= mysql_select(thd, &fake_select_lex->ref_pointer_array,
                               &result_table_list,
                               0, item_list, NULL,