From f48b42e77657dd2e27380201631fd0f137863b85 Mon Sep 17 00:00:00 2001 From: Gleb Shchepa Date: Wed, 8 Oct 2008 02:34:00 +0500 Subject: Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while ``FLUSH TABLES WITH READ LOCK'' Concurrent execution of 1) multitable update with a NATURAL/USING join and 2) a such query as "FLUSH TABLES WITH READ LOCK" or "ALTER TABLE" of updating table led to a server crash. The mysql_multi_update_prepare() function call is optimized to lock updating tables only, so it postpones locking to the last, and if locking fails, it does cleanup of modified syntax structures and repeats a query analysis. However, that cleanup procedure was incomplete for NATURAL/USING join syntax data: 1) some Field_item items pointed into freed table structures, and 2) the TABLE_LIST::join_columns fields was not reset. Major change: short-living Field *Natural_join_column::table_field has been replaced with long-living Item*. mysql-test/r/lock_multi.result: Added test case for bug #38691. mysql-test/t/lock_multi.test: Added test case for bug #38691. sql/item.cc: Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while ``FLUSH TABLES WITH READ LOCK'' The Item_field constructor has been modified to allocate and copy original database/table/field names always (not during PS preparation/1st execution only), because an initialization of Item_field items with a pointer to short-living Field structures is a common practice. sql/sql_base.cc: Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while ``FLUSH TABLES WITH READ LOCK'' 1) Type adjustment for Natural_join_column::table_field (Field to Item_field); 2) The setup_natural_join_row_types function has been updated to take into account new first_natural_join_processing flag to skip unnecessary reinitialization of Natural_join_column::join_columns during table reopening after lock_tables() failure (like the 'first_execution' flag for PS). sql/sql_lex.cc: Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while ``FLUSH TABLES WITH READ LOCK'' Initialization of the new st_select_lex::first_natural_join_processing flag has been added. sql/sql_lex.h: Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while ``FLUSH TABLES WITH READ LOCK'' The st_select_lex::first_natural_join_processing flag has been added to skip unnecessary rebuilding of NATURAL/USING JOIN structures during table reopening after lock_tables failure. sql/sql_update.cc: Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while ``FLUSH TABLES WITH READ LOCK'' Extra cleanup calls have been added to reset Natural_join_column::table_field items. sql/table.cc: Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while ``FLUSH TABLES WITH READ LOCK'' Type adjustment for Natural_join_column::table_field (Field to Item_field). sql/table.h: Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while ``FLUSH TABLES WITH READ LOCK'' Type of the Natural_join_column::table_field field has been changed from Field that points into short-living TABLE memory to long-living Item_field that can be linked to (fixed) reopened table. --- mysql-test/r/lock_multi.result | 16 ++++++ mysql-test/t/lock_multi.test | 119 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 135 insertions(+) (limited to 'mysql-test') diff --git a/mysql-test/r/lock_multi.result b/mysql-test/r/lock_multi.result index 079f92ca420..d46aea24ac3 100644 --- a/mysql-test/r/lock_multi.result +++ b/mysql-test/r/lock_multi.result @@ -99,3 +99,19 @@ kill query ERROR 70100: Query execution was interrupted unlock tables; drop table t1; +CREATE TABLE t1 ( +a int(11) unsigned default NULL, +b varchar(255) default NULL, +UNIQUE KEY a (a), +KEY b (b) +); +INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3); +CREATE TABLE t2 SELECT * FROM t1; +CREATE TABLE t3 SELECT * FROM t1; +# test altering of columns that multiupdate doesn't use +# normal mode +# PS mode +# test altering of columns that multiupdate uses +# normal mode +# PS mode +DROP TABLE t1, t2, t3; diff --git a/mysql-test/t/lock_multi.test b/mysql-test/t/lock_multi.test index 649c1a4efbd..fe22efeb8c2 100644 --- a/mysql-test/t/lock_multi.test +++ b/mysql-test/t/lock_multi.test @@ -281,4 +281,123 @@ unlock tables; connection default; drop table t1; +# +# Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while +# ``FLUSH TABLES WITH READ LOCK'' +# + +--connection default +CREATE TABLE t1 ( + a int(11) unsigned default NULL, + b varchar(255) default NULL, + UNIQUE KEY a (a), + KEY b (b) +); + +INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3); +CREATE TABLE t2 SELECT * FROM t1; +CREATE TABLE t3 SELECT * FROM t1; + +--echo # test altering of columns that multiupdate doesn't use + +--echo # normal mode + +--disable_query_log +let $i = 100; +while ($i) { +--dec $i + +--connection writer + send UPDATE t2 INNER JOIN (t1 JOIN t3 USING(a)) USING(a) + SET a = NULL WHERE t1.b <> t2.b; + +--connection locker + ALTER TABLE t2 ADD COLUMN (c INT); + ALTER TABLE t2 DROP COLUMN c; + +--connection writer +--reap +} + +--echo # PS mode + +--connection writer +PREPARE stmt FROM 'UPDATE t2 INNER JOIN (t1 JOIN t3 USING(a)) USING(a) + SET a = NULL WHERE t1.b <> t2.b'; + +let $i = 100; +while ($i) { +--dec $i + +--connection writer +--send EXECUTE stmt + +--connection locker + ALTER TABLE t2 ADD COLUMN (c INT); + ALTER TABLE t2 DROP COLUMN c; + +--connection writer +--reap +} +--enable_query_log + + +--echo # test altering of columns that multiupdate uses + +--echo # normal mode + +--connection default + +--disable_query_log +let $i = 100; +while ($i) { + dec $i; + +--connection locker +--error 0,1060 + ALTER TABLE t2 ADD COLUMN a int(11) unsigned default NULL; + UPDATE t2 SET a=b; + +--connection writer +--send UPDATE t2 INNER JOIN (t1 JOIN t3 USING(a)) USING(a) SET a = NULL WHERE t1.b <> t2.b + +--connection locker +--error 0,1091 + ALTER TABLE t2 DROP COLUMN a; + +--connection writer +--error 0,1054 +--reap +} +--enable_query_log + +--echo # PS mode + +--disable_query_log +let $i = 100; +while ($i) { + dec $i; + +--connection locker +--error 0,1060 + ALTER TABLE t2 ADD COLUMN a int(11) unsigned default NULL; + UPDATE t2 SET a=b; + +--connection writer + PREPARE stmt FROM 'UPDATE t2 INNER JOIN (t1 JOIN t3 USING(a)) USING(a) SET a = NULL WHERE t1.b <> t2.b'; +--send EXECUTE stmt + +--connection locker +--error 0,1091 + ALTER TABLE t2 DROP COLUMN a; + +--connection writer +--error 0,1054 +--reap + +} +--enable_query_log +--connection default +DROP TABLE t1, t2, t3; + # End of 5.0 tests -- cgit v1.2.1