MDEV-5153: Server crashes in Item_ref::fix_fields on 2nd execution of PS with...

MDEV-5153: Server crashes in Item_ref::fix_fields on 2nd execution of PS with LEFT JOIN and MERGE view or SELECT SQ

1. Transformation of row IN subquery made the same as single value.
2. replace_where_subcondition() made working on several layers of OR/AND because it called on expression before fix_fields().

mysql-test/r/view.result

@@ -4709,6 +4709,37 @@ q	1	q
 q	1	q
 drop view v1;
 drop table t1,t2;
+#
+# MDEV-5153: Server crashes in Item_ref::fix_fields on 2nd execution
+# of PS with LEFT JOIN and MERGE view or SELECT SQ
+#
+CREATE TABLE t1 (i1 INT, c1 VARCHAR(6)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (1,'foo'),(2,'bar');
+CREATE TABLE t2 (c2 VARCHAR(6)) ENGINE=MyISAM;
+INSERT INTO t2 VALUES ('foobar'),('qux');
+CREATE ALGORITHM=MERGE VIEW v1 AS SELECT * FROM t1 WHERE ( c1 ) IN ( SELECT c2 FROM t2 ) AND i1 <= 2 ;
+PREPARE stmt FROM 'SELECT * FROM t1 LEFT JOIN v1 ON (v1.i1 = t1.i1)';
+EXECUTE stmt;
+i1	c1	i1	c1
+1	foo	NULL	NULL
+2	bar	NULL	NULL
+EXECUTE stmt;
+i1	c1	i1	c1
+1	foo	NULL	NULL
+2	bar	NULL	NULL
+drop view v1;
+CREATE ALGORITHM=MERGE VIEW v1 AS SELECT * FROM t1 WHERE ( c1, c1 ) IN ( SELECT c2, c2 FROM t2 ) AND i1 <= 2 ;
+EXECUTE stmt;
+i1	c1	i1	c1
+1	foo	NULL	NULL
+2	bar	NULL	NULL
+EXECUTE stmt;
+i1	c1	i1	c1
+1	foo	NULL	NULL
+2	bar	NULL	NULL
+deallocate prepare stmt;
+drop view v1;
+drop table t1,t2;
 # -----------------------------------------------------------------
 # -- End of 5.3 tests.
 # -----------------------------------------------------------------

mysql-test/t/view.test

@@ -4647,6 +4647,34 @@ SELECT * FROM t2 LEFT JOIN v1 ON ( c=b AND a IN ( 1,6 ) );
 drop view v1;
 drop table t1,t2;
 
+--echo #
+--echo # MDEV-5153: Server crashes in Item_ref::fix_fields on 2nd execution
+--echo # of PS with LEFT JOIN and MERGE view or SELECT SQ
+--echo #
+
+CREATE TABLE t1 (i1 INT, c1 VARCHAR(6)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (1,'foo'),(2,'bar');
+
+CREATE TABLE t2 (c2 VARCHAR(6)) ENGINE=MyISAM;
+INSERT INTO t2 VALUES ('foobar'),('qux');
+
+CREATE ALGORITHM=MERGE VIEW v1 AS SELECT * FROM t1 WHERE ( c1 ) IN ( SELECT c2 FROM t2 ) AND i1 <= 2 ;
+
+PREPARE stmt FROM 'SELECT * FROM t1 LEFT JOIN v1 ON (v1.i1 = t1.i1)';
+
+EXECUTE stmt;
+EXECUTE stmt;
+
+drop view v1;
+CREATE ALGORITHM=MERGE VIEW v1 AS SELECT * FROM t1 WHERE ( c1, c1 ) IN ( SELECT c2, c2 FROM t2 ) AND i1 <= 2 ;
+
+EXECUTE stmt;
+EXECUTE stmt;
+
+deallocate prepare stmt;
+drop view v1;
+drop table t1,t2;
+
 --echo # -----------------------------------------------------------------
 --echo # -- End of 5.3 tests.
 --echo # -----------------------------------------------------------------

sql/item_cmpfunc.cc

@@ -1436,9 +1436,11 @@ bool Item_in_optimizer::eval_not_null_tables(uchar *opt_arg)
 
 bool Item_in_optimizer::fix_left(THD *thd, Item **ref)
 {
+  DBUG_ENTER("Item_in_optimizer::fix_left");
   if ((!args[0]->fixed && args[0]->fix_fields(thd, args)) ||
       (!cache && !(cache= Item_cache::get_cache(args[0]))))
-    return 1;
+    DBUG_RETURN(1);
+  DBUG_PRINT("info", ("actual fix fields"));
 
   cache->setup(args[0]);
   if (cache->cols() == 1)
@@ -1460,10 +1462,13 @@ bool Item_in_optimizer::fix_left(THD *thd, Item **ref)
       {
         my_error(ER_NOT_SUPPORTED_YET, MYF(0),
                  "SUBQUERY in ROW in left expression of IN/ALL/ANY");
-        return 1;
+        DBUG_RETURN(1);
       }
       if (args[0]->element_index(i)->used_tables())
+      {
 	((Item_cache *)cache->element_index(i))->set_used_tables(OUTER_REF_TABLE_BIT);
+        cache->set_used_tables(OUTER_REF_TABLE_BIT);
+      }
       else
 	((Item_cache *)cache->element_index(i))->set_used_tables(0);
     }
@@ -1477,7 +1482,7 @@ bool Item_in_optimizer::fix_left(THD *thd, Item **ref)
     cache->store(args[0]);
     cache->cache_value();
   }
-  return 0;
+  DBUG_RETURN(0);
 }
 
 

sql/item_subselect.cc

@@ -2177,11 +2177,11 @@ Item_in_subselect::create_row_in_to_exists_cond(JOIN * join,
         DBUG_RETURN(true);
       Item *item_eq=
         new Item_func_eq(new
-                         Item_ref(&select_lex->context,
-                                  (*optimizer->get_cache())->
-                                  addr(i),
-                                  (char *)"<no matter>",
-                                  (char *)in_left_expr_name),
+                         Item_direct_ref(&select_lex->context,
+                                         (*optimizer->get_cache())->
+                                         addr(i),
+                                         (char *)"<no matter>",
+                                         (char *)in_left_expr_name),
                          new
                          Item_ref(&select_lex->context,
                                   select_lex->ref_pointer_array + i,
@@ -2462,7 +2462,7 @@ bool Item_in_subselect::inject_in_to_exists_cond(JOIN *join_arg)
 bool
 Item_in_subselect::select_in_like_transformer(JOIN *join)
 {
-  Query_arena *arena, backup;
+  Query_arena *arena= 0, backup;
   SELECT_LEX *current= thd->lex->current_select;
   const char *save_where= thd->where;
   bool trans_res= true;
@@ -2484,9 +2484,6 @@ Item_in_subselect::select_in_like_transformer(JOIN *join)
     }
   }
 
-  if (changed)
-    DBUG_RETURN(false);
-
   thd->where= "IN/ALL/ANY subquery";
 
   /*
@@ -2497,25 +2494,29 @@ Item_in_subselect::select_in_like_transformer(JOIN *join)
     note: we won't need Item_in_optimizer when handling degenerate cases
     like "... IN (SELECT 1)"
   */
+  arena= thd->activate_stmt_arena_if_needed(&backup);
   if (!optimizer)
   {
-    arena= thd->activate_stmt_arena_if_needed(&backup);
     result= (!(optimizer= new Item_in_optimizer(left_expr, this)));
-    if (arena)
-      thd->restore_active_arena(arena, &backup);
     if (result)
-      goto err;
+      goto out;
   }
 
   thd->lex->current_select= current->return_after_parsing();
-  result= (!left_expr->fixed &&
-           left_expr->fix_fields(thd, optimizer->arguments()));
+  result= optimizer->fix_left(thd, optimizer->arguments());
   /* fix_fields can change reference to left_expr, we need reassign it */
   left_expr= optimizer->arguments()[0];
-
   thd->lex->current_select= current;
+
+  if (changed)
+  {
+    trans_res= false;
+    goto out;
+  }
+
+
   if (result)
-    goto err;
+    goto out;
 
   /*
     Both transformers call fix_fields() only for Items created inside them,
@@ -2524,7 +2525,6 @@ Item_in_subselect::select_in_like_transformer(JOIN *join)
     of Item, we have to call fix_fields() for it only with original arena to
     avoid memory leack)
   */
-  arena= thd->activate_stmt_arena_if_needed(&backup);
   if (left_expr->cols() == 1)
     trans_res= single_value_transformer(join);
   else
@@ -2539,9 +2539,9 @@ Item_in_subselect::select_in_like_transformer(JOIN *join)
     }
     trans_res= row_value_transformer(join);
   }
+out:
   if (arena)
     thd->restore_active_arena(arena, &backup);
-err:
   thd->where= save_where;
   DBUG_RETURN(trans_res);
 }

sql/opt_subselect.cc

@@ -1252,11 +1252,11 @@ void get_delayed_table_estimates(TABLE *table,
    @brief Replaces an expression destructively inside the expression tree of
    the WHERE clase.
 
-   @note Because of current requirements for semijoin flattening, we do not
-   need to recurse here, hence this function will only examine the top-level
-   AND conditions. (see JOIN::prepare, comment starting with "Check if the 
-   subquery predicate can be executed via materialization".
-   
+   @note We substitute AND/OR structure because it was copied by
+   copy_andor_structure and some changes could be done in the copy but
+   should be left permanent, also there could be several layers of AND over
+   AND and OR over OR because ::fix_field() possibly is not called.
+
    @param join The top-level query.
    @param old_cond The expression to be replaced.
    @param new_cond The expression to be substituted.
@@ -1284,13 +1284,20 @@ static bool replace_where_subcondition(JOIN *join, Item **expr,
     Item *item;
     while ((item= li++))
     {
-      if (item == old_cond) 
+      if (item == old_cond)
       {
         li.replace(new_cond);
         if (do_fix_fields)
           new_cond->fix_fields(join->thd, li.ref());
         return FALSE;
       }
+      else if (item->type() == Item::COND_ITEM)
+      {
+        DBUG_ASSERT(!(*expr)->fixed);
+        replace_where_subcondition(join, li.ref(),
+                                   old_cond, new_cond,
+                                   do_fix_fields);
+      }
     }
   }
   /*