#At file:///data0/my/darnaut/mysql-repo/work/41110-5.0/ based on revid:azundris@stripped
2760 Davi Arnaut 2009-02-24
Bug#41110: crash with handler command when used concurrently with alter table
Bug#41112: crash in mysql_ha_close_table/get_lock_data with alter table
The problem is that the server wasn't handling robustly failures
to re-open a table during a HANDLER .. READ statement. If the
table needed to be re-opened due to it's storage engine being
altered to one that doesn't support HANDLER, a reference (dangling
pointer) to a closed table could be left in place and accessed in
later attempts to fetch from the table using the handler. Also,
if the server failed to set a error message if the re-open
failed. These problems could lead to server crashes or hangs.
The solution is to remove any references to a closed table and
to set a error if reopening a table during a HANDLER .. READ
There is no test case in this change set as the test depends on
a testing feature only available on 5.1 and later.
Remove redundant reopen check.
Set errors even if reopening table.
Reset TABLE_LIST::table reference when the table is closed.
=== modified file 'sql/sql_handler.cc'
--- a/sql/sql_handler.cc 2007-10-12 13:55:46 +0000
+++ b/sql/sql_handler.cc 2009-02-24 09:15:21 +0000
@@ -151,6 +151,9 @@ static void mysql_ha_close_table(THD *th
+ /* Mark table as closed, ready for re-open if necessary. */
+ tables->table= NULL;
@@ -168,8 +171,7 @@ static void mysql_ha_close_table(THD *th
'reopen' is set when a handler table is to be re-opened. In this case,
'tables' is the pointer to the hashed TABLE_LIST object which has been
saved on the original open.
- 'reopen' is also used to suppress the sending of an 'ok' message or
- error messages.
+ 'reopen' is also used to suppress the sending of an 'ok' message.
@@ -205,8 +207,7 @@ bool mysql_ha_open(THD *thd, TABLE_LIST
strlen(tables->alias) + 1))
DBUG_PRINT("info",("duplicate '%s'", tables->alias));
- if (! reopen)
- my_error(ER_NONUNIQ_TABLE, MYF(0), tables->alias);
+ my_error(ER_NONUNIQ_TABLE, MYF(0), tables->alias);
@@ -251,8 +252,7 @@ bool mysql_ha_open(THD *thd, TABLE_LIST
/* There can be only one table in '*tables'. */
if (! (tables->table->file->table_flags() & HA_CAN_SQL_HANDLER))
- if (! reopen)
- my_error(ER_ILLEGAL_HA, MYF(0), tables->alias);
+ my_error(ER_ILLEGAL_HA, MYF(0), tables->alias);
@@ -464,8 +464,7 @@ retry:
- mysql_ha_close_table(thd, tables);
- hash_tables->table= NULL;
+ mysql_ha_close_table(thd, hash_tables);
The lock might have been aborted, we need to manually reset
thd->some_tables_deleted because handler's tables are closed
Attachment: [text/bzr-bundle] firstname.lastname@example.org
|• bzr commit into mysql-5.0-bugteam branch (Davi.Arnaut:2760) Bug#41110Bug#41112||Davi Arnaut||24 Feb|