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5.1 repository of alik. When alik does a push these changes will
be propagated to the main repository and, within 24 hours after the
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see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html
ChangeSet@stripped, 2007-10-17 10:05:50+04:00, anozdrin@station. +7 -0
Patch for BUG#31111: --read-only crashes MySQL (events fail to load).
There actually were several problems here:
- WRITE-lock is required to load events from the mysql.event table,
but in the read-only mode an ordinary user can not acquire it;
- Security_context::master_access attribute was not properly
initialized in Security_context::init(), which led to differences
in behavior with and without debug configure options.
- if the server failed to load events from mysql.event, it:
- forgot to close the mysql.event table, that led to the coredump,
described in the bug report;
- did not deinitialize the replication module, that lead to
memory-lost warning on exit.
The patch is to fix all these problems:
- Use the super-user to acquire WRITE-lock on the mysql.even table;
- The WRITE-lock is acquired by the event scheduler in two cases:
- on initial loading of events from the database;
- when an event has been executed, so its attributes should
be updated.
Other cases when WRITE-lock is needed for the mysql.event table
happen under the user account. So, nothing should be changed there:
The user is able to create/update/drop an event only if he is
a super-user.
- Initialize Security_context::master_access;
- Close the mysql.event table in case something went wrong;
- Deinitialize the replication module on exit.
mysql-test/r/bug31111.result@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +53 -0
Result file.
mysql-test/r/bug31111.result@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +0 -0
mysql-test/t/bug31111-master.opt@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +1 -0
A test case for BUG#31111.
mysql-test/t/bug31111-master.opt@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +0 -0
mysql-test/t/bug31111.test@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +101 -0
A test case for BUG#31111.
mysql-test/t/bug31111.test@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +0 -0
sql/event_db_repository.cc@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +23 -3
1. Close tables if something went wrong in simple_open_n_lock_tables();
2. Open the mysql.event table as the super user to be able to acquire
WRITE-lock in the read-only mode.
sql/events.cc@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +15 -1
Open the mysql.event table as the super user to be able to acquire
WRITE-lock in the read-only mode.
sql/mysqld.cc@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +3 -0
If something went wrong with event loading, we the replication
module should be deinitialized prior to general exit procedure.
sql/sql_class.cc@stripped, 2007-10-17 10:05:48+04:00, anozdrin@station. +1 -0
Initialize Security_context::master_acces.
diff -Nrup a/mysql-test/r/bug31111.result b/mysql-test/r/bug31111.result
--- /dev/null Wed Dec 31 16:00:00 196900
+++ b/mysql-test/r/bug31111.result 2007-10-17 10:05:48 +04:00
@@ -0,0 +1,53 @@
+SELECT @@global.read_only;
+@@global.read_only
+1
+
+GRANT EVENT ON *.* TO u1@localhost;
+
+#
+# Connection: con1 (u1@localhost/test).
+#
+
+CREATE EVENT e1 ON SCHEDULE AT '2020-01-01 00:00:00' DO SET @a = 1;
+ERROR HY000: The MySQL server is running with the --read-only option so it cannot execute this statement
+
+ALTER EVENT e1 COMMENT 'comment';
+ERROR HY000: The MySQL server is running with the --read-only option so it cannot execute this statement
+
+DROP EVENT e1;
+ERROR HY000: The MySQL server is running with the --read-only option so it cannot execute this statement
+
+#
+# Connection: default.
+#
+
+CREATE EVENT e1 ON SCHEDULE AT '2020-01-01 00:00:00' DO SET @a = 1;
+
+ALTER EVENT e1 COMMENT 'comment';
+
+DROP EVENT e1;
+
+CREATE EVENT e1 ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 1 SECOND DO SET @a = 1;
+CREATE EVENT e2 ON SCHEDULE EVERY 1 SECOND DO SET @a = 1;
+
+SELECT name, last_executed IS NULL FROM mysql.event;
+name last_executed IS NULL
+e1 1
+e2 1
+
+SET GLOBAL EVENT_SCHEDULER = ON;
+
+# Sleeping for 3 seconds...
+
+SELECT name, last_executed IS NULL FROM mysql.event;
+name last_executed IS NULL
+e2 0
+
+SET GLOBAL EVENT_SCHEDULER = OFF;
+
+DROP EVENT e1;
+ERROR HY000: Unknown event 'e1'
+
+DROP EVENT e2;
+
+# That is it.
diff -Nrup a/mysql-test/t/bug31111-master.opt b/mysql-test/t/bug31111-master.opt
--- /dev/null Wed Dec 31 16:00:00 196900
+++ b/mysql-test/t/bug31111-master.opt 2007-10-17 10:05:48 +04:00
@@ -0,0 +1 @@
+--read-only
diff -Nrup a/mysql-test/t/bug31111.test b/mysql-test/t/bug31111.test
--- /dev/null Wed Dec 31 16:00:00 196900
+++ b/mysql-test/t/bug31111.test 2007-10-17 10:05:48 +04:00
@@ -0,0 +1,101 @@
+#
+# BUG#31111: --read-only crashes MySQL (events fail to load).
+#
+# It actually does not matter what SQL statements are here. The thing is being
+# tested is that the server is able to start.
+#
+
+SELECT @@global.read_only;
+
+--echo
+
+# Check that an ordinary user can not create/update/drop events.
+
+GRANT EVENT ON *.* TO u1@localhost;
+
+--echo
+
+--echo #
+--echo # Connection: con1 (u1@localhost/test).
+--echo #
+
+--connect(con1,localhost,u1,,test)
+
+--echo
+
+--error ER_OPTION_PREVENTS_STATEMENT
+CREATE EVENT e1 ON SCHEDULE AT '2020-01-01 00:00:00' DO SET @a = 1;
+
+--echo
+
+--error ER_OPTION_PREVENTS_STATEMENT
+ALTER EVENT e1 COMMENT 'comment';
+
+--echo
+
+--error ER_OPTION_PREVENTS_STATEMENT
+DROP EVENT e1;
+
+--echo
+
+--disconnect con1
+
+--echo #
+--echo # Connection: default.
+--echo #
+
+--connection default
+
+# Check that the super user still can create/update/drop events.
+
+--echo
+
+CREATE EVENT e1 ON SCHEDULE AT '2020-01-01 00:00:00' DO SET @a = 1;
+
+--echo
+
+ALTER EVENT e1 COMMENT 'comment';
+
+--echo
+
+DROP EVENT e1;
+
+--echo
+
+# Check that the scheduler is able to update event.
+
+CREATE EVENT e1 ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 1 SECOND DO SET @a = 1;
+CREATE EVENT e2 ON SCHEDULE EVERY 1 SECOND DO SET @a = 1;
+
+--echo
+
+SELECT name, last_executed IS NULL FROM mysql.event;
+
+--echo
+
+SET GLOBAL EVENT_SCHEDULER = ON;
+
+--echo
+
+--echo # Sleeping for 3 seconds...
+--sleep 3
+
+--echo
+
+SELECT name, last_executed IS NULL FROM mysql.event;
+
+--echo
+
+SET GLOBAL EVENT_SCHEDULER = OFF;
+
+--echo
+
+--error ER_EVENT_DOES_NOT_EXIST
+DROP EVENT e1;
+
+--echo
+
+DROP EVENT e2;
+
+--echo
+--echo # That is it.
diff -Nrup a/sql/event_db_repository.cc b/sql/event_db_repository.cc
--- a/sql/event_db_repository.cc 2007-08-25 12:43:10 +04:00
+++ b/sql/event_db_repository.cc 2007-10-17 10:05:48 +04:00
@@ -525,6 +525,9 @@ Event_db_repository::fill_schema_events(
- whether this open mode would work under LOCK TABLES, or inside a
stored function or trigger.
+ Note, if the table can not be open, this operation will clean out all
+ table-related objects from the memory.
+
@param[in] thd Thread context
@param[in] lock_type How to lock the table
@param[out] table We will store the open table here
@@ -544,7 +547,10 @@ Event_db_repository::open_event_table(TH
tables.init_one_table("mysql", "event", lock_type);
if (simple_open_n_lock_tables(thd, &tables))
+ {
+ close_thread_tables(thd, FALSE, FALSE);
DBUG_RETURN(TRUE);
+ }
*table= tables.table;
tables.table->use_all_columns();
@@ -984,7 +990,8 @@ update_timing_fields_for_event(THD *thd,
{
TABLE *table= NULL;
Field **fields;
- int ret= 1;
+ bool ret= TRUE;
+ ulong saved_master_access;
DBUG_ENTER("Event_db_repository::update_timing_fields_for_event");
@@ -995,7 +1002,20 @@ update_timing_fields_for_event(THD *thd,
if (thd->current_stmt_binlog_row_based)
thd->clear_current_stmt_binlog_row_based();
- if (open_event_table(thd, TL_WRITE, &table))
+ /*
+ NOTE: even if we run in read-only mode, we should be able to lock the
+ mysql.event table for writing. In order to achieve this, we should call
+ mysql_lock_tables() under the super user.
+ */
+
+ saved_master_access= thd->security_ctx->master_access;
+ thd->security_ctx->master_access |= SUPER_ACL;
+
+ ret= open_event_table(thd, TL_WRITE, &table);
+
+ thd->security_ctx->master_access= saved_master_access;
+
+ if (ret)
goto end;
fields= table->field;
@@ -1028,7 +1048,7 @@ update_timing_fields_for_event(THD *thd,
goto end;
}
- ret= 0;
+ ret= FALSE;
end:
if (table)
diff -Nrup a/sql/events.cc b/sql/events.cc
--- a/sql/events.cc 2007-08-15 19:08:40 +04:00
+++ b/sql/events.cc 2007-10-17 10:05:48 +04:00
@@ -1124,11 +1124,25 @@ Events::load_events_from_db(THD *thd)
READ_RECORD read_record_info;
bool ret= TRUE;
uint count= 0;
+ ulong saved_master_access;
DBUG_ENTER("Events::load_events_from_db");
DBUG_PRINT("enter", ("thd: 0x%lx", (long) thd));
- if (db_repository->open_event_table(thd, TL_WRITE, &table))
+ /*
+ NOTE: even if we run in read-only mode, we should be able to lock the
+ mysql.event table for writing. In order to achieve this, we should call
+ mysql_lock_tables() under the super user.
+ */
+
+ saved_master_access= thd->security_ctx->master_access;
+ thd->security_ctx->master_access |= SUPER_ACL;
+
+ ret= db_repository->open_event_table(thd, TL_WRITE, &table);
+
+ thd->security_ctx->master_access= saved_master_access;
+
+ if (ret)
{
sql_print_error("Event Scheduler: Failed to open table mysql.event");
DBUG_RETURN(TRUE);
diff -Nrup a/sql/mysqld.cc b/sql/mysqld.cc
--- a/sql/mysqld.cc 2007-08-28 11:02:53 +04:00
+++ b/sql/mysqld.cc 2007-10-17 10:05:48 +04:00
@@ -3930,7 +3930,10 @@ we force server id to 2, but this MySQL
create_maintenance_thread();
if (Events::init(opt_noacl))
+ {
+ end_slave();
unireg_abort(1);
+ }
sql_print_information(ER(ER_STARTUP),my_progname,server_version,
((unix_sock == INVALID_SOCKET) ? (char*) ""
diff -Nrup a/sql/sql_class.cc b/sql/sql_class.cc
--- a/sql/sql_class.cc 2007-10-15 16:42:39 +04:00
+++ b/sql/sql_class.cc 2007-10-17 10:05:48 +04:00
@@ -2404,6 +2404,7 @@ void Security_context::init()
host= user= priv_user= ip= 0;
host_or_ip= "connecting host";
priv_host[0]= '\0';
+ master_access= 0;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
db_access= NO_ACCESS;
#endif
| Thread |
|---|
| • bk commit into 5.1 tree (anozdrin:1.2600) BUG#31111 | Alexander Nozdrin | 17 Oct |
