From 6a0d03fce76616dd10e8d6bd83c19af26f8c5874 Mon Sep 17 00:00:00 2001 From: Chaithra Gopalareddy Date: Fri, 24 Feb 2012 11:53:36 +0530 Subject: [PATCH] Bug#13012483:EXPLAIN EXTENDED, PREPARED STATEMENT, CRASH IN CHECK_SIMPLE_EQUALITY PROBLEM: Crash in "check_simple_equality" when using a subquery with "IN" and "ALL" in prepare. ANALYSIS: Crash can be reproduced using a simplified query like this one: prepare s from "select 1 from g1 where 1 < all ( select @:=(1 in (select 1 from g1)) from g1)"; This bug is currently present only on 5.5.and 5.1. Its fixed as part of work log(#1110) in 5.6. We are taking one change to fix this in 5.5 and 5.1. Problem seems to be present because we are trying to evaluate "is_null" on an argument which is part of a subquery (In Item_is_not_null_test::update_used_tables()). But the condition to evaluate is only when we do not have a sub query present, which means to say that "with_subselect" is not set. With respect to the above query, we create an object of type "Item_in_optimizer" which by definition is always associated with a subquery. While in 5.6 we set "with_subselect" to true for "Item_in_optimizer" object, we do not do the same in 5.5. This results in the evaluation for "is_null" resulting in a coredump. So, we are now setting "with_subselect" to true for "Item_in_optimizer" in 5.1 and 5.5. mysql-test/r/func_in.result: Result file changes for the test case added mysql-test/t/func_in.test: Test case added for Bug#13012483 sql/item_cmpfunc.h: Changed Item_in_optimizer::Item_in_optimizer( ) to set "with_subselect" to true --- mysql-test/r/func_in.result | 10 ++++++++++ mysql-test/t/func_in.test | 13 +++++++++++++ sql/item_cmpfunc.h | 2 +- 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/mysql-test/r/func_in.result b/mysql-test/r/func_in.result index 0b6117581f3..7f0e607e789 100644 --- a/mysql-test/r/func_in.result +++ b/mysql-test/r/func_in.result @@ -776,4 +776,14 @@ SELECT 1 IN (YEAR(FROM_UNIXTIME(NULL)) ,1); 1 IN (YEAR(FROM_UNIXTIME(NULL)) ,1) 1 # +# +# Bug#13012483: EXPLAIN EXTENDED, PREPARED STATEMENT, CRASH IN CHECK_SIMPLE_EQUALITY +# +CREATE TABLE t1 (a INT); +PREPARE s FROM "SELECT 1 FROM t1 WHERE 1 < ALL (SELECT @:= (1 IN (SELECT 1 FROM t1)) FROM t1)"; +EXECUTE s; +1 +DROP TABLE t1; +# End of test BUG#13012483 +# End of 5.1 tests diff --git a/mysql-test/t/func_in.test b/mysql-test/t/func_in.test index 08469b37967..dd4194e2a4e 100644 --- a/mysql-test/t/func_in.test +++ b/mysql-test/t/func_in.test @@ -562,4 +562,17 @@ SELECT 1 IN (YEAR(FROM_UNIXTIME(NULL)) ,1); --echo # +--echo # +--echo # Bug#13012483: EXPLAIN EXTENDED, PREPARED STATEMENT, CRASH IN CHECK_SIMPLE_EQUALITY +--echo # + +CREATE TABLE t1 (a INT); +PREPARE s FROM "SELECT 1 FROM t1 WHERE 1 < ALL (SELECT @:= (1 IN (SELECT 1 FROM t1)) FROM t1)"; +EXECUTE s; + +DROP TABLE t1; + +--echo # End of test BUG#13012483 + +--echo # --echo End of 5.1 tests diff --git a/sql/item_cmpfunc.h b/sql/item_cmpfunc.h index 4d8cadfcce9..b185bf02790 100644 --- a/sql/item_cmpfunc.h +++ b/sql/item_cmpfunc.h @@ -254,7 +254,7 @@ public: Item_in_optimizer(Item *a, Item_in_subselect *b): Item_bool_func(a, my_reinterpret_cast(Item *)(b)), cache(0), save_cache(0), result_for_null_param(UNKNOWN) - {} + { with_subselect= true; } bool fix_fields(THD *, Item **); bool fix_left(THD *thd, Item **ref); bool is_null();