mirror of
https://github.com/MariaDB/server.git
synced 2025-01-16 12:02:42 +01:00
22630531cb
---------------------------------------------------------- revno: 2617.69.21 committer: Konstantin Osipov <kostja@sun.com> branch nick: 5.4-4284-1-assert timestamp: Thu 2009-08-13 20:13:55 +0400 message: A fix and a test case for Bug#46610 "MySQL 5.4.4: MyISAM MRG engine crash on auto-repair of child". Also fixes Bug#42862 "Crash on failed attempt to open a children of a merge table". MERGE engine needs to extend the global table list with TABLE_LIST elements for child tables, so that they are opened and locked. Previously these table list elements were allocated in memory of ha_myisammrg object (MERGE engine handler). That would lead to access to freed memory in recover_from_failed_open_table_attempt(), which would try to recover a MERGE table child (MyISAM table) and use for that TABLE_LIST of that child. But by the time recover_from_failed_open_table_attempt() is invoked, ha_myisammrg object that owns this TABLE_LIST may be destroyed, and thus TABLE_LIST memory freed. The fix is to ensure that TABLE_LIST elements that are added to the global table list (lex->query_tables) are always allocated in thd->mem_root, which is not destroyed until end of execution. If previously TABLE_LIST elements were allocated at ha_myisammrg::open() (i.e. when the TABLE object was created and added to the table cache), now they are allocated in ha_myisammrg::add_chidlren_list() (i.e. right after "open" of the merge parent in open_tables()). We still create a list of children names at ha_myisammrg::open() to use as a basis for creation of TABLE_LISTs, that allows to avoid reading the merge handler data file on every execution.
1 line
23 B
Text
1 line
23 B
Text
--myisam-recover=force
|