MDEV-26009 Server crash when calling twice procedure using FOR-loop

The problem was that instructions sp_instr_cursor_copy_struct and
sp_instr_copen uses the same lex, adding and removing "tail" of
prelocked tables and forgetting that tail of all tables is kept in
LEX::query_tables_last. If the LEX used only by one instruction
or the query do not have prelocked tables it is not important.
But to work correctly in all cases LEX::query_tables_last should
be reset to make new tables added in the correct list (after last
table in the LEX instead after last table of the prelocking "tail"
which was cut).

Author: sanja-byelkin

mysql-test/main/sp-cursor.result

@@ -737,3 +737,66 @@ rec.en1
 c
 DROP PROCEDURE p1;
 DROP TABLE t1;
+#
+# MDEV-26009: Server crash when calling twice procedure using FOR-loop
+#
+CREATE TABLE t1 ( id int, name varchar(24));
+INSERT INTO t1 values (1, 'x'), (2, 'y'), (3, 'z');
+create function get_name(_id int) returns varchar(24)
+return (select name from t1 where id = _id);
+select get_name(id) from t1;
+get_name(id)
+x
+y
+z
+create  procedure test_proc()
+begin
+declare _cur cursor for select get_name(id) from t1;
+for row in _cur do select 1; end for;
+end;
+^^
+call test_proc();
+1
+1
+1
+1
+1
+1
+call test_proc();
+1
+1
+1
+1
+1
+1
+drop procedure test_proc;
+drop function get_name;
+drop table t1;
+CREATE TABLE t1 (id int, name varchar(24));
+INSERT INTO t1 (id, name) VALUES (1, 'x'),(2, 'y'),(3, 'z');
+create function get_name(_id int) returns varchar(24) 
+return (select name from t1 where id = _id);
+create view v1 as select get_name(id) from t1;
+create  procedure test_proc()
+begin
+declare _cur cursor for select 1 from v1;   
+for row in _cur do select 1; end for;
+end$$
+call test_proc();
+1
+1
+1
+1
+1
+1
+call test_proc();
+1
+1
+1
+1
+1
+1
+drop procedure test_proc;
+drop view v1;
+drop function get_name;
+drop table t1;

mysql-test/main/sp-cursor.test

@@ -744,3 +744,59 @@ DELIMITER ;$$
 CALL p1();
 DROP PROCEDURE p1;
 DROP TABLE t1;
+
+
+--echo #
+--echo # MDEV-26009: Server crash when calling twice procedure using FOR-loop
+--echo #
+
+
+CREATE TABLE t1 ( id int, name varchar(24));
+INSERT INTO t1 values (1, 'x'), (2, 'y'), (3, 'z');
+
+create function get_name(_id int) returns varchar(24)
+    return (select name from t1 where id = _id);
+
+select get_name(id) from t1;
+
+delimiter ^^;
+
+create  procedure test_proc()
+begin
+    declare _cur cursor for select get_name(id) from t1;
+    for row in _cur do select 1; end for;
+end;
+^^
+delimiter ;^^
+
+call test_proc();
+call test_proc();
+
+drop procedure test_proc;
+drop function get_name;
+drop table t1;
+
+
+CREATE TABLE t1 (id int, name varchar(24));
+INSERT INTO t1 (id, name) VALUES (1, 'x'),(2, 'y'),(3, 'z');
+ 
+create function get_name(_id int) returns varchar(24) 
+	return (select name from t1 where id = _id);
+ 
+create view v1 as select get_name(id) from t1;
+ 
+delimiter $$;
+create  procedure test_proc()
+begin
+    declare _cur cursor for select 1 from v1;   
+    for row in _cur do select 1; end for;
+end$$
+delimiter ;$$
+
+call test_proc();
+call test_proc();
+
+drop procedure test_proc;
+drop view v1;
+drop function get_name;
+drop table t1;

sql/sp_head.cc

@@ -3486,6 +3486,7 @@ sp_lex_keeper::reset_lex_and_exec_core(THD *thd, uint *nextp,
     lex_query_tables_own_last= m_lex->query_tables_own_last;
     prelocking_tables= *lex_query_tables_own_last;
     *lex_query_tables_own_last= NULL;
+    m_lex->query_tables_last= m_lex->query_tables_own_last;
     m_lex->mark_as_requiring_prelocking(NULL);
   }
   thd->rollback_item_tree_changes();