MDEV-15247: Crash when SET NAMES 'utf8' is set

In this case we are accessing incorrect memory when we have mergeable semi-joins.
In the case when we have mergeable semi joins parent select will have a table count
of all the tables in that select plus all the tables involved in the IN-subquery.
But this table count does not include the "sjm table" (only includes the inner and outer tables)
denotes as <subquery#> in explain.

3 files changed, 180 insertions, 1 deletions

diff --git a/mysql-test/r/subselect_sj2_mat.result b/mysql-test/r/subselect_sj2_mat.result
index c629c8196c7..c27beb295b8 100644
--- a/mysql-test/r/subselect_sj2_mat.result
+++ b/mysql-test/r/subselect_sj2_mat.result
@@ -1691,3 +1691,93 @@ id
 12
 13
 drop table t1;
+#
+# MDEV-15247: Crash when SET NAMES 'utf8' is set
+#
+CREATE TABLE t1 (
+id_category int unsigned,
+id_product int unsigned,
+PRIMARY KEY (id_category,id_product)
+) ENGINE=MyISAM;
+INSERT INTO `t1` VALUES (31,216), (31,215), (31,214), (31,213), (31,212), (32,211), (32,210), (32,209), (32,208), (29,207), (30,315372), (2,161), (2,132), (33,315380), (31,315371), (29,315370), (29,315373), (29,315369), (29,315374), (29,315368), (29,315375), (29,315367), (29,183), (29,182), (30,177), (29,315376), (13,315365), (2,167), (2,315357), (2,164), (2,159), (2,131), (2,127), (14,315364), (27,315363), (29,205), (29,204), (29,203), (29,202), (29,201), (29,200), (29,199), (29,198), (29,197), (29,196), (29,195), (29,194), (29,193), (29,192), (29,191), (29,190), (29,189), (14,188), (29,187), (29,186), (29,185), (29,184), (29,315377), (29,315378), (29,181), (33,315379), (29,179), (30,178), (29,180), (30,176), (30,175), (30,174), (30,173), (30,172), (11,171), (27,315357), (23,108), (23,102);
+CREATE TABLE t2 (
+id_product int,
+id_t2 int,
+KEY id_t2 (id_t2),
+KEY id_product (id_product)
+) ENGINE=MyISAM;
+INSERT INTO `t2` VALUES (11,31), (11,31), (11,31), (11,32), (11,32),
+(11,32), (10,26), (11,32), (10,28), (11,32), (10,29), (11,33), (10,26),
+(11,33), (10,27), (9,23), (11,32), (10,26), (8,18), (7,15), (11,32),
+(10,28), (11,32), (10,28), (11,32), (10,29), (11,32), (10,29), (8,19),
+(7,16), (8,18), (7,16), (8,20), (7,16), (11,32), (10,28), (8,19),
+(7,16), (8,20), (7,16), (11,32), (10,29), (8,19), (7,16), (8,20),
+(7,16), (10,27), (9,23), (10,27), (9,23), (10,27), (9,23), (11,32),
+(10,27), (11,32), (10,27), (8,18), (7,15), (10,26), (9,24), (8,19),
+(7,16), (10,26), (9,23), (8,19), (7,16), (8,18), (7,16), (8,18), (7,16),
+(9,23), (8,18), (9,23), (8,19), (7,16), (7,16), (8,19), (7,16), (11,31),
+(10,27), (9,24), (11,31), (10,27), (9,23), (8,19), (11,31), (10,26), (9,24),
+(8,19), (11,31), (10,26), (9,25), (8,18), (11,31), (10,26), (9,23), (8,19),
+(11,31), (10,26), (9,23), (8,18), (11,31), (10,30), (9,23), (8,18), (11,31),
+(10,30), (9,23), (8,19), (11,31), (10,26), (9,25), (8,19), (8,21), (11,32),
+(10,26), (9,22), (8,19), (11,32), (10,26), (9,22), (8,18), (11,32), (10,26),
+(9,22), (8,20), (11,33), (10,26), (9,22), (8,19), (11,33), (10,26), (9,22),
+(8,18), (11,33), (10,26), (9,22), (8,20), (11,32), (10,26), (9,24), (8,19),
+(11,32), (10,26), (9,25), (8,19), (11,32), (10,26), (9,25), (8,18), (11,32),
+(10,26), (9,23), (8,18), (11,32), (10,30), (9,23), (8,18), (11,32), (10,30),
+(9,23), (8,19), (11,32), (10,26), (9,23), (8,19), (11,32), (10,27), (9,23),
+(11,32), (10,27), (9,23), (11,32), (10,27), (9,23), (10,26), (9,22), (8,19),
+(7,15), (10,26), (9,22), (8,20), (7,15), (10,26), (9,22), (8,18), (7,15),
+(8,19), (10,26), (10,26), (11,33), (10,26), (11,33), (10,26), (11,33),
+(10,27), (11,33), (10,27), (11,31), (10,26), (11,31), (10,26), (8,18),
+(7,15), (9,23), (9,23), (9,24), (8,21), (7,15), (7,15), (7,15), (7,15),
+(7,15), (7,15), (7,15), (7,15), (7,15), (8,18), (7,17), (8,18), (7,17), (8,19), (8,19);
+CREATE TABLE t3 (
+id_product int unsigned,
+PRIMARY KEY (id_product)
+) ENGINE=MyISAM;
+INSERT INTO t3 VALUES 
+(102),(103),(104),(105),(106),(107),(108),(109),(110),
+(315371),(315373),(315374),(315375),(315376),(315377),
+(315378),(315379),(315380);
+CREATE TABLE t4 (
+id_product int  not null,
+id_shop int,
+PRIMARY KEY (id_product,id_shop)
+) ENGINE=MyISAM ;
+INSERT INTO t4 VALUES 
+(202,1),(201,1),(200,1),(199,1),(198,1),(197,1),(196,1),(195,1),
+(194,1),(193,1),(192,1),(191,1),(190,1),(189,1),(188,1),(187,1),
+(186,1),(185,1),(184,1),(183,1),(182,1),(181,1),(179,1),(178,1),
+(177,1),(176,1),(126,1),(315380,1);
+CREATE TABLE t5 (id_product int) ENGINE=MyISAM;
+INSERT INTO `t5` VALUES 
+(652),(668),(669),(670),(671),(673),(674),(675),(676),
+(677),(679),(680),(681),(682),(683),(684),(685),(686);
+explain
+SELECT * FROM t3 
+JOIN t4 ON (t4.id_product = t3.id_product AND t4.id_shop = 1)
+JOIN t1 ON (t1.id_product = t3.id_product)
+LEFT JOIN t5 ON (t5.id_product = t3.id_product)
+WHERE 1=1
+AND t3.id_product IN (SELECT id_product FROM t2 t2_1 WHERE t2_1.id_t2 = 32) 
+AND t3.id_product IN (SELECT id_product FROM t2 t2_2 WHERE t2_2.id_t2 = 15)  
+AND t3.id_product IN (SELECT id_product FROM t2 t2_3 WHERE t2_3.id_t2 = 18 OR t2_3.id_t2 = 19)
+AND t3.id_product IN (SELECT id_product FROM t2 t2_4 WHERE t2_4.id_t2 = 34 OR t2_4.id_t2 = 23) 
+AND t3.id_product IN (SELECT id_product FROM t2 t2_5 WHERE t2_5.id_t2 = 29 OR t2_5.id_t2 = 28 OR t2_5.id_t2 = 26);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	index	NULL	PRIMARY	8	NULL	73	Using index
+1	PRIMARY	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.id_product	1	Using index
+1	PRIMARY	<subquery5>	eq_ref	distinct_key	distinct_key	4	func	1	Using where
+1	PRIMARY	<subquery4>	eq_ref	distinct_key	distinct_key	4	func	1	Using where
+1	PRIMARY	<subquery3>	eq_ref	distinct_key	distinct_key	4	func	1	Using where
+1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	4	func	1	Using where
+1	PRIMARY	t4	eq_ref	PRIMARY	PRIMARY	8	test.t1.id_product,const	1	Using where; Using index
+1	PRIMARY	<subquery6>	eq_ref	distinct_key	distinct_key	4	func	1	Using where
+1	PRIMARY	t5	ALL	NULL	NULL	NULL	NULL	18	Using where; Using join buffer (flat, BNL join)
+5	MATERIALIZED	t2_4	range	id_t2,id_product	id_t2	5	NULL	18	Using index condition; Using where
+4	MATERIALIZED	t2_3	range	id_t2,id_product	id_t2	5	NULL	32	Using index condition; Using where
+3	MATERIALIZED	t2_2	ref	id_t2,id_product	id_t2	5	const	12	
+2	MATERIALIZED	t2_1	ref	id_t2,id_product	id_t2	5	const	50	
+6	MATERIALIZED	t2_5	range	id_t2,id_product	id_t2	5	NULL	30	Using index condition; Using where
+drop table t1,t2,t3,t4,t5;
diff --git a/mysql-test/t/subselect_sj2_mat.test b/mysql-test/t/subselect_sj2_mat.test
index 0665cdf68fe..68a888012f2 100644
--- a/mysql-test/t/subselect_sj2_mat.test
+++ b/mysql-test/t/subselect_sj2_mat.test
@@ -345,3 +345,90 @@ WHERE (
         (t.id IN (0,4,12,13,1,10,3,11))
 );
 drop table t1;
+
+--echo #
+--echo # MDEV-15247: Crash when SET NAMES 'utf8' is set
+--echo #
+
+CREATE TABLE t1 (
+  id_category int unsigned,
+  id_product int unsigned,
+  PRIMARY KEY (id_category,id_product)
+) ENGINE=MyISAM;
+
+INSERT INTO `t1` VALUES (31,216), (31,215), (31,214), (31,213), (31,212), (32,211), (32,210), (32,209), (32,208), (29,207), (30,315372), (2,161), (2,132), (33,315380), (31,315371), (29,315370), (29,315373), (29,315369), (29,315374), (29,315368), (29,315375), (29,315367), (29,183), (29,182), (30,177), (29,315376), (13,315365), (2,167), (2,315357), (2,164), (2,159), (2,131), (2,127), (14,315364), (27,315363), (29,205), (29,204), (29,203), (29,202), (29,201), (29,200), (29,199), (29,198), (29,197), (29,196), (29,195), (29,194), (29,193), (29,192), (29,191), (29,190), (29,189), (14,188), (29,187), (29,186), (29,185), (29,184), (29,315377), (29,315378), (29,181), (33,315379), (29,179), (30,178), (29,180), (30,176), (30,175), (30,174), (30,173), (30,172), (11,171), (27,315357), (23,108), (23,102);
+ 
+CREATE TABLE t2 (
+  id_product int,
+  id_t2 int,
+  KEY id_t2 (id_t2),
+  KEY id_product (id_product)
+) ENGINE=MyISAM;
+ 
+INSERT INTO `t2` VALUES (11,31), (11,31), (11,31), (11,32), (11,32),
+(11,32), (10,26), (11,32), (10,28), (11,32), (10,29), (11,33), (10,26),
+(11,33), (10,27), (9,23), (11,32), (10,26), (8,18), (7,15), (11,32),
+(10,28), (11,32), (10,28), (11,32), (10,29), (11,32), (10,29), (8,19),
+(7,16), (8,18), (7,16), (8,20), (7,16), (11,32), (10,28), (8,19),
+(7,16), (8,20), (7,16), (11,32), (10,29), (8,19), (7,16), (8,20),
+(7,16), (10,27), (9,23), (10,27), (9,23), (10,27), (9,23), (11,32),
+(10,27), (11,32), (10,27), (8,18), (7,15), (10,26), (9,24), (8,19),
+(7,16), (10,26), (9,23), (8,19), (7,16), (8,18), (7,16), (8,18), (7,16),
+(9,23), (8,18), (9,23), (8,19), (7,16), (7,16), (8,19), (7,16), (11,31),
+(10,27), (9,24), (11,31), (10,27), (9,23), (8,19), (11,31), (10,26), (9,24),
+(8,19), (11,31), (10,26), (9,25), (8,18), (11,31), (10,26), (9,23), (8,19),
+(11,31), (10,26), (9,23), (8,18), (11,31), (10,30), (9,23), (8,18), (11,31),
+(10,30), (9,23), (8,19), (11,31), (10,26), (9,25), (8,19), (8,21), (11,32),
+(10,26), (9,22), (8,19), (11,32), (10,26), (9,22), (8,18), (11,32), (10,26),
+(9,22), (8,20), (11,33), (10,26), (9,22), (8,19), (11,33), (10,26), (9,22),
+(8,18), (11,33), (10,26), (9,22), (8,20), (11,32), (10,26), (9,24), (8,19),
+(11,32), (10,26), (9,25), (8,19), (11,32), (10,26), (9,25), (8,18), (11,32),
+(10,26), (9,23), (8,18), (11,32), (10,30), (9,23), (8,18), (11,32), (10,30),
+(9,23), (8,19), (11,32), (10,26), (9,23), (8,19), (11,32), (10,27), (9,23),
+(11,32), (10,27), (9,23), (11,32), (10,27), (9,23), (10,26), (9,22), (8,19),
+(7,15), (10,26), (9,22), (8,20), (7,15), (10,26), (9,22), (8,18), (7,15),
+(8,19), (10,26), (10,26), (11,33), (10,26), (11,33), (10,26), (11,33),
+(10,27), (11,33), (10,27), (11,31), (10,26), (11,31), (10,26), (8,18),
+(7,15), (9,23), (9,23), (9,24), (8,21), (7,15), (7,15), (7,15), (7,15),
+(7,15), (7,15), (7,15), (7,15), (7,15), (8,18), (7,17), (8,18), (7,17), (8,19), (8,19);
+
+CREATE TABLE t3 (
+  id_product int unsigned,
+  PRIMARY KEY (id_product)
+) ENGINE=MyISAM;
+ 
+INSERT INTO t3 VALUES 
+(102),(103),(104),(105),(106),(107),(108),(109),(110),
+(315371),(315373),(315374),(315375),(315376),(315377),
+(315378),(315379),(315380);
+
+CREATE TABLE t4 (
+  id_product int  not null,
+  id_shop int,
+  PRIMARY KEY (id_product,id_shop)
+) ENGINE=MyISAM ;
+ 
+INSERT INTO t4 VALUES 
+(202,1),(201,1),(200,1),(199,1),(198,1),(197,1),(196,1),(195,1),
+(194,1),(193,1),(192,1),(191,1),(190,1),(189,1),(188,1),(187,1),
+(186,1),(185,1),(184,1),(183,1),(182,1),(181,1),(179,1),(178,1),
+(177,1),(176,1),(126,1),(315380,1);
+
+CREATE TABLE t5 (id_product int) ENGINE=MyISAM;
+INSERT INTO `t5` VALUES 
+(652),(668),(669),(670),(671),(673),(674),(675),(676),
+(677),(679),(680),(681),(682),(683),(684),(685),(686);
+ 
+explain
+SELECT * FROM t3 
+  JOIN t4 ON (t4.id_product = t3.id_product AND t4.id_shop = 1)
+  JOIN t1 ON (t1.id_product = t3.id_product)
+LEFT JOIN t5 ON (t5.id_product = t3.id_product)
+WHERE 1=1
+AND t3.id_product IN (SELECT id_product FROM t2 t2_1 WHERE t2_1.id_t2 = 32) 
+AND t3.id_product IN (SELECT id_product FROM t2 t2_2 WHERE t2_2.id_t2 = 15)  
+AND t3.id_product IN (SELECT id_product FROM t2 t2_3 WHERE t2_3.id_t2 = 18 OR t2_3.id_t2 = 19)
+AND t3.id_product IN (SELECT id_product FROM t2 t2_4 WHERE t2_4.id_t2 = 34 OR t2_4.id_t2 = 23) 
+AND t3.id_product IN (SELECT id_product FROM t2 t2_5 WHERE t2_5.id_t2 = 29 OR t2_5.id_t2 = 28 OR t2_5.id_t2 = 26);
+ 
+drop table t1,t2,t3,t4,t5;
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 39209f04c9f..1ec6cca7c5b 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -9592,7 +9592,7 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
     table_map current_map;
     i= join->const_tables;
     for (tab= first_depth_first_tab(join); tab;
-         tab= next_depth_first_tab(join, tab), i++)
+         tab= next_depth_first_tab(join, tab))
     {
       bool is_hj;
       /*
@@ -10063,6 +10063,8 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
         }
         first_inner_tab= first_inner_tab->first_upper;       
       }
+      if (!tab->bush_children)
+        i++;
     }
   }
   DBUG_RETURN(0);