In statement-based or mixed-mode replication, use DROP TEMPORARY TABLE
to drop multiple tables causes different errors on master and slave,
when one or more of these tables do not exist. Because when executed
on slave, it would automatically add IF EXISTS to the query to ignore
all ER_BAD_TABLE_ERROR errors.
To fix the problem, do not add IF EXISTS when executing DROP TEMPORARY
TABLE on the slave, and clear the ER_BAD_TABLE_ERROR error after
execution if the query does not expect any errors.
mysql-test/suite/rpl/r/rpl_drop_temp.result:
Updated for the patch of bug#49137.
mysql-test/suite/rpl/t/rpl_drop_temp.test:
Added the test file to verify if DROP MULTI TEMPORARY TABLE
will cause different errors on master and slave, when one or
more of these tables do not exist.
sql/log_event.cc:
Added code to handle above cases which are
removed from sql_parse.cc
sql/sql_parse.cc:
Remove the code to issue the 'Unknown table' error,
if the temporary table does not exist when dropping
it on slave. The above cases decribed in comments
will be handled later in log_event.cc.
In statement-based or mixed-mode replication, use DROP TEMPORARY TABLE
to drop multiple tables causes different errors on master and slave,
when one or more of these tables do not exist. Because when executed
on slave, it would automatically add IF EXISTS to the query to ignore
all ER_BAD_TABLE_ERROR errors.
To fix the problem, do not add IF EXISTS when executing DROP TEMPORARY
TABLE on the slave, and clear the ER_BAD_TABLE_ERROR error after
execution if the query does not expect any errors.
In statement-based or mixed-mode replication, use DROP TEMPORARY TABLE
to drop multiple tables causes different errors on master and slave,
when one or more of these tables do not exist. Because when executed
on slave, it would automatically add IF EXISTS to the query to ignore
all ER_BAD_TABLE_ERROR errors.
To fix the problem, do not add IF EXISTS when executing DROP TEMPORARY
TABLE on the slave, and clear the ER_BAD_TABLE_ERROR error after
execution if the query does not expect any errors.
mysql-test/r/rpl_drop_temp.result:
Updated for the patch of bug#49137.
mysql-test/t/rpl_drop_temp.test:
Added the test file to verify if DROP MULTI TEMPORARY TABLE
will cause different errors on master and slave, when one or
more of these tables do not exist.
sql/log_event.cc:
Added code to handle above cases which are
removed from sql_parse.cc
sql/sql_parse.cc:
Remove the code to issue the 'Unknown table' error,
if the temporary table does not exist when dropping
it on slave. The above cases decribed in comments
will be handled later in log_event.cc.
In statement-based or mixed-mode replication, use DROP TEMPORARY TABLE
to drop multiple tables causes different errors on master and slave,
when one or more of these tables do not exist. Because when executed
on slave, it would automatically add IF EXISTS to the query to ignore
all ER_BAD_TABLE_ERROR errors.
To fix the problem, do not add IF EXISTS when executing DROP TEMPORARY
TABLE on the slave, and clear the ER_BAD_TABLE_ERROR error after
execution if the query does not expect any errors.
3655 Jon Olav Hauglid 2009-10-19
Bug #30977 Concurrent statement using stored function and DROP FUNCTION
breaks SBR
Bug #48246 assert in close_thread_table
Implement a fix for:
Bug #41804 purge stored procedure cache causes mysterious hang for many
minutes
Bug #49972 Crash in prepared statements
The problem was that concurrent execution of DML statements that
use stored functions and DDL statements that drop/modify the same
function might result in incorrect binary log in statement (and
mixed) mode and therefore break replication.
This patch fixes the problem by introducing metadata locking for
stored procedures and functions. This is similar to what is done
in Bug#25144 for views. Procedures and functions now are
locked using metadata locks until the transaction is either
committed or rolled back. This prevents other statements from
modifying the procedure/function while it is being executed. This
provides commit ordering - guaranteeing serializability across
multiple transactions and thus fixes the reported binlog problem.
Note that we do not take locks for top-level CALLs. This means
that procedures called directly are not protected from changes by
simultaneous DDL operations so they are executed at the state they
had at the time of the CALL. By not taking locks for top-level
CALLs, we still allow transactions to be started inside
procedures.
This patch also changes stored procedure cache invalidation.
Upon a change of cache version, we no longer invalidate the entire
cache, but only those routines which we use, only when a statement
is executed that uses them.
This patch also changes the logic of prepared statement validation.
A stored procedure used by a prepared statement is now validated
only once a metadata lock has been acquired. A version mismatch
causes a flush of the obsolete routine from the cache and
statement reprepare.
Incompatible changes:
1) ER_LOCK_DEADLOCK is reported for a transaction trying to access
a procedure/function that is locked by a DDL operation in
another connection.
2) Procedure/function DDL operations are now prohibited in LOCK
TABLES mode as exclusive locks must be taken all at once and
LOCK TABLES provides no way to specifiy procedures/functions to
be locked.
Test cases have been added to sp-lock.test and rpl_sp.test.
Work on this bug has very much been a team effort and this patch
includes and is based on contributions from Davi Arnaut, Dmitry
Lenev, Magne Mæhre and Konstantin Osipov.
mysql-test/r/ps_ddl.result:
Update results (Bug#30977).
mysql-test/r/ps_ddl1.result:
Update results (Bug#30977).
mysql-test/r/sp-error.result:
Update results (Bug#30977).
mysql-test/r/sp-lock.result:
Update results (Bug#30977).
mysql-test/suite/rpl/r/rpl_sp.result:
Update results (Bug#30977).
mysql-test/suite/rpl/t/rpl_sp.test:
Add a test case for Bug#30977.
mysql-test/t/ps_ddl.test:
Update comments. We no longer re-prepare a prepared statement
when a stored procedure used in top-level CALL is changed.
mysql-test/t/ps_ddl1.test:
Modifying stored procedure p1 no longer invalidates prepared
statement "call p1" -- we can re-use the prepared statement
without invalidation.
mysql-test/t/sp-error.test:
Use a constant for an error value.
mysql-test/t/sp-lock.test:
Add test coverage for Bug#30977.
sql/lock.cc:
Implement lock_routine_name() - a way to acquire an
exclusive metadata lock (ex- name-lock) on
stored procedure/function.
sql/sp.cc:
Change semantics of sp_cache_routine() -- now it has an option
to make sure that the routine that is cached is up to date (has
the latest sp cache version).
Add sp_cache_invalidate() to sp_drop_routine(), where it was
missing (a bug!).
Acquire metadata locks for SP DDL (ALTER/CREATE/DROP). This is
the core of the fix for Bug#30977.
Since caching and cache invalidation scheme was changed, make
sure we don't invalidate the SP cache in the middle of a stored
routine execution. At the same time, make sure we don't access
stale data due to lack of invalidation.
For that, change ALTER FUNCTION/PROCEDURE to not use the cache,
and SHOW PROCEDURE CODE/SHOW CREATE PROCEDURE/FUNCTION to always
read an up to date version of the routine from the cache.
sql/sp.h:
Add a helper wrapper around sp_cache_routine().
sql/sp_cache.cc:
Implement new sp_cache_version() and sp_cache_flush_obsolete().
Now we flush stale routines individually, rather than all at once.
sql/sp_cache.h:
Update signatures of sp_cache_version() and sp_cache_flush_obsolete().
sql/sp_head.cc:
Add a default initialization of sp_head::m_sp_cache_version.
Remove a redundant sp_head::create().
sql/sp_head.h:
Add m_sp_cache_version to sp_head class - we now
keep track of every routine in the stored procedure cache, rather than
of the entire cache.
sql/sql_base.cc:
Implement prelocking for stored routines. Validate stored
routines after they were locked.
Flush obsolete routines upon next access, one by one, not all at once
(Bug#41804).
Style fixes.
sql/sql_class.h:
Rename a Open_table_context method.
sql/sql_parse.cc:
Make sure stored procedures DDL commits the active transaction
(issues an implicit commit before and after).
Remove sp_head::create(), a pure redundancy.
Move the semantical check during alter routine inside sp_update_routine() code in order to:
- avoid using SP cache during update, it may be obsolete.
- speed up and simplify the update procedure.
Remove sp_cache_flush_obsolete() calls, we no longer flush the entire
cache, ever, stale routines are flushed before next use, one at a time.
sql/sql_prepare.cc:
Move routine metadata validation to open_and_process_routine().
Fix Bug#49972 (don't swap flags at reprepare).
Reset Sroutine_hash_entries in reinit_stmt_before_use().
Remove SP cache invalidation, it's now done by open_tables().
sql/sql_show.cc:
Fix a warning: remove an unused label.
sql/sql_table.cc:
Reset mdl_request.ticket for tickets acquired for routines inlined
through a view, in CHECK TABLE statement, to satisfy an MDL assert.
sql/sql_update.cc:
Move the cleanup of "translation items" to close_tables_for_reopen(),
since it's needed in all cases when we back off, not just
the back-off in multi-update. This fixes a bug when the server
would crash on attempt to back off when opening tables
for a statement that uses information_schema tables.
3655 Jon Olav Hauglid 2009-10-19
Bug #30977 Concurrent statement using stored function and DROP FUNCTION
breaks SBR
Bug #48246 assert in close_thread_table
Implement a fix for:
Bug #41804 purge stored procedure cache causes mysterious hang for many
minutes
Bug #49972 Crash in prepared statements
The problem was that concurrent execution of DML statements that
use stored functions and DDL statements that drop/modify the same
function might result in incorrect binary log in statement (and
mixed) mode and therefore break replication.
This patch fixes the problem by introducing metadata locking for
stored procedures and functions. This is similar to what is done
in Bug#25144 for views. Procedures and functions now are
locked using metadata locks until the transaction is either
committed or rolled back. This prevents other statements from
modifying the procedure/function while it is being executed. This
provides commit ordering - guaranteeing serializability across
multiple transactions and thus fixes the reported binlog problem.
Note that we do not take locks for top-level CALLs. This means
that procedures called directly are not protected from changes by
simultaneous DDL operations so they are executed at the state they
had at the time of the CALL. By not taking locks for top-level
CALLs, we still allow transactions to be started inside
procedures.
This patch also changes stored procedure cache invalidation.
Upon a change of cache version, we no longer invalidate the entire
cache, but only those routines which we use, only when a statement
is executed that uses them.
This patch also changes the logic of prepared statement validation.
A stored procedure used by a prepared statement is now validated
only once a metadata lock has been acquired. A version mismatch
causes a flush of the obsolete routine from the cache and
statement reprepare.
Incompatible changes:
1) ER_LOCK_DEADLOCK is reported for a transaction trying to access
a procedure/function that is locked by a DDL operation in
another connection.
2) Procedure/function DDL operations are now prohibited in LOCK
TABLES mode as exclusive locks must be taken all at once and
LOCK TABLES provides no way to specifiy procedures/functions to
be locked.
Test cases have been added to sp-lock.test and rpl_sp.test.
Work on this bug has very much been a team effort and this patch
includes and is based on contributions from Davi Arnaut, Dmitry
Lenev, Magne Mæhre and Konstantin Osipov.
"HANDLER statements within a transaction might lead to deadlocks".
Introduce a notion of a sentinel to MDL_context. A sentinel
is a ticket that separates all tickets in the context into two
groups: before and after it. Currently we can have (and need) only
one designated sentinel -- it separates all locks taken by LOCK
TABLE or HANDLER statement, which must survive COMMIT and ROLLBACK
and all other locks, which must be released at COMMIT or ROLLBACK.
The tricky part is maintaining the sentinel up to date when
someone release its corresponding ticket. This can happen, e.g.
if someone issues DROP TABLE under LOCK TABLES (generally,
see all calls to release_all_locks_for_name()).
MDL_context::release_ticket() is modified to take care of it.
******
A fix and a test case for Bug#46224 "HANDLER statements within a
transaction might lead to deadlocks".
An attempt to mix HANDLER SQL statements, which are transaction-
agnostic, an open multi-statement transaction,
and DDL against the involved tables (in a concurrent connection)
could lead to a deadlock. The deadlock would occur when
HANDLER OPEN or HANDLER READ would have to wait on a conflicting
metadata lock. If the connection that issued HANDLER statement
also had other metadata locks (say, acquired in scope of a
transaction), a classical deadlock situation of mutual wait
could occur.
Incompatible change: entering LOCK TABLES mode automatically
closes all open HANDLERs in the current connection.
Incompatible change: previously an attempt to wait on a lock
in a connection that has an open HANDLER statement could wait
indefinitely/deadlock. After this patch, an error ER_LOCK_DEADLOCK
is produced.
The idea of the fix is to merge thd->handler_mdl_context
with the main mdl_context of the connection, used for transactional
locks. This makes deadlock detection possible, since all waits
with locks are "visible" and available to analysis in a single
MDL context of the connection.
Since HANDLER locks and transactional locks have a different life
cycle -- HANDLERs are explicitly open and closed, and so
are HANDLER locks, explicitly acquired and released, whereas
transactional locks "accumulate" till the end of a transaction
and are released only with COMMIT, ROLLBACK and ROLLBACK TO SAVEPOINT,
a concept of "sentinel" was introduced to MDL_context.
All locks, HANDLER and others, reside in the same linked list.
However, a selected element of the list separates locks with
different life cycle. HANDLER locks always reside at the
end of the list, after the sentinel. Transactional locks are
prepended to the beginning of the list, before the sentinel.
Thus, ROLLBACK, COMMIT or ROLLBACK TO SAVEPOINT, only
release those locks that reside before the sentinel. HANDLER locks
must be released explicitly as part of HANDLER CLOSE statement,
or an implicit close.
The same approach with sentinel
is also employed for LOCK TABLES locks. Since HANDLER and LOCK TABLES
statement has never worked together, the implementation is
made simple and only maintains one sentinel, which is used either
for HANDLER locks, or for LOCK TABLES locks.
mysql-test/include/handler.inc:
Add test coverage for Bug#46224 "HANDLER statements within a
transaction might lead to deadlocks".
Extended HANDLER coverage to cover a mix of HANDLER, transactions
and DDL statements.
mysql-test/r/handler_innodb.result:
Update results (Bug#46224).
mysql-test/r/handler_myisam.result:
Update results (Bug#46224).
sql/lock.cc:
Remove thd->some_tables_deleted, it's never used.
sql/log_event.cc:
No need to check for thd->locked_tables_mode,
it's done inside release_transactional_locks().
sql/mdl.cc:
Implement the concept of HANDLER and LOCK TABLES "sentinel".
Implement a method to clone an acquired ticket.
Do not return tickets beyond the sentinel when acquiring
locks, create a copy.
Remove methods to merge and backup MDL_context, they are now
not used (Hurra!). This opens a path to a proper constructor
and destructor of class MDL_context (to be done in a separate
patch).
Modify find_ticket() to provide information about where
the ticket position is with regard to the sentinel.
sql/mdl.h:
Add declarations necessary for the implementation of the concept
of "sentinel", a dedicated ticket separating transactional and
non-transactional locks.
sql/mysql_priv.h:
Add mark_tmp_table_for_reuse() declaration,
a function to "close" a single session (temporary) table.
sql/sql_base.cc:
Remove thd->some_tables_deleted.
Modify deadlock-prevention asserts and deadlock detection
heuristics to take into account that from now on HANDLER locks
reside in the same locking context.
Add broadcast_refresh() to mysql_notify_thread_having_shared_lock():
this is necessary for the case when a thread having a shared lock
is asleep in tdc_wait_for_old_versions(). This situation is only
possible with HANDLER t1 OPEN; FLUSH TABLE (since all over code paths
that lead to tdc_wait_for_old_versions() always have an
empty MDL_context). Previously the server would simply deadlock
in this situation.
sql/sql_class.cc:
Remove now unused member "THD::some_tables_deleted".
Move mysql_ha_cleanup() a few lines above in THD::cleanup()
to make sure that all handlers are closed when it's time to
destroy the MDL_context of this connection.
Remove handler_mdl_context and handler_tables.
sql/sql_class.h:
Remove THD::handler_tables, THD::handler_mdl_context,
THD::some_tables_deleted.
sql/sql_handler.cc:
Remove thd->handler_tables.
Remove thd->handler_mdl_context.
Rewrite mysql_ha_open() to have no special provision for MERGE
tables, now that we don't have to manipulate with thd->handler_tables
it's easy to do.
Remove dead code.
Fix a bug in mysql_ha_flush() when we would always flush
a temporary HANDLER when mysql_ha_flush() is called (actually
mysql_ha_flush() never needs to flush temporary tables).
sql/sql_insert.cc:
Update a comment, no more thd->some_tables_deleted.
sql/sql_parse.cc:
Implement an incompatible change: entering LOCK TABLES closes
active HANDLERs, if any.
Now that we have a sentinel, we don't need to check
for thd->locked_tables_mode when releasing metadata locks in
COMMIT/ROLLBACK.
sql/sql_plist.h:
Add new (now necessary) methods to the list class.
sql/sql_prepare.cc:
Make sure we don't release HANDLER locks when rollback to a
savepoint, set to not keep locks taken at PREPARE.
sql/sql_servers.cc:
Update to a new signature of MDL_context::release_all_locks().
sql/sql_table.cc:
Remove thd->some_tables_deleted.
sql/transaction.cc:
Add comments.
Make sure rollback to (MDL) savepoint works under LOCK TABLES and
with HANDLER tables.
"HANDLER statements within a transaction might lead to deadlocks".
Introduce a notion of a sentinel to MDL_context. A sentinel
is a ticket that separates all tickets in the context into two
groups: before and after it. Currently we can have (and need) only
one designated sentinel -- it separates all locks taken by LOCK
TABLE or HANDLER statement, which must survive COMMIT and ROLLBACK
and all other locks, which must be released at COMMIT or ROLLBACK.
The tricky part is maintaining the sentinel up to date when
someone release its corresponding ticket. This can happen, e.g.
if someone issues DROP TABLE under LOCK TABLES (generally,
see all calls to release_all_locks_for_name()).
MDL_context::release_ticket() is modified to take care of it.
******
A fix and a test case for Bug#46224 "HANDLER statements within a
transaction might lead to deadlocks".
An attempt to mix HANDLER SQL statements, which are transaction-
agnostic, an open multi-statement transaction,
and DDL against the involved tables (in a concurrent connection)
could lead to a deadlock. The deadlock would occur when
HANDLER OPEN or HANDLER READ would have to wait on a conflicting
metadata lock. If the connection that issued HANDLER statement
also had other metadata locks (say, acquired in scope of a
transaction), a classical deadlock situation of mutual wait
could occur.
Incompatible change: entering LOCK TABLES mode automatically
closes all open HANDLERs in the current connection.
Incompatible change: previously an attempt to wait on a lock
in a connection that has an open HANDLER statement could wait
indefinitely/deadlock. After this patch, an error ER_LOCK_DEADLOCK
is produced.
The idea of the fix is to merge thd->handler_mdl_context
with the main mdl_context of the connection, used for transactional
locks. This makes deadlock detection possible, since all waits
with locks are "visible" and available to analysis in a single
MDL context of the connection.
Since HANDLER locks and transactional locks have a different life
cycle -- HANDLERs are explicitly open and closed, and so
are HANDLER locks, explicitly acquired and released, whereas
transactional locks "accumulate" till the end of a transaction
and are released only with COMMIT, ROLLBACK and ROLLBACK TO SAVEPOINT,
a concept of "sentinel" was introduced to MDL_context.
All locks, HANDLER and others, reside in the same linked list.
However, a selected element of the list separates locks with
different life cycle. HANDLER locks always reside at the
end of the list, after the sentinel. Transactional locks are
prepended to the beginning of the list, before the sentinel.
Thus, ROLLBACK, COMMIT or ROLLBACK TO SAVEPOINT, only
release those locks that reside before the sentinel. HANDLER locks
must be released explicitly as part of HANDLER CLOSE statement,
or an implicit close.
The same approach with sentinel
is also employed for LOCK TABLES locks. Since HANDLER and LOCK TABLES
statement has never worked together, the implementation is
made simple and only maintains one sentinel, which is used either
for HANDLER locks, or for LOCK TABLES locks.
Bug#16565 mysqld --help --verbose does not order variablesBug#20413 sql_slave_skip_counter is not shown in show variables
Bug#20415 Output of mysqld --help --verbose is incomplete
Bug#25430 variable not found in SELECT @@global.ft_max_word_len;
Bug#32902 plugin variables don't know their names
Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
Bug#34829 No default value for variable and setting default does not raise error
Bug#34834 ? Is accepted as a valid sql mode
Bug#34878 Few variables have default value according to documentation but error occurs
Bug#34883 ft_boolean_syntax cant be assigned from user variable to global var.
Bug#37187 `INFORMATION_SCHEMA`.`GLOBAL_VARIABLES`: inconsistent status
Bug#40988 log_output_basic.test succeeded though syntactically false.
Bug#41010 enum-style command-line options are not honoured (maria.maria-recover fails)
Bug#42103 Setting key_buffer_size to a negative value may lead to very large allocations
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
Bug#44797 plugins w/o command-line options have no disabling option in --help
Bug#46314 string system variables don't support expressions
Bug#46470 sys_vars.max_binlog_cache_size_basic_32 is broken
Bug#46586 When using the plugin interface the type "set" for options caused a crash.
Bug#47212 Crash in DBUG_PRINT in mysqltest.cc when trying to print octal number
Bug#48758 mysqltest crashes on sys_vars.collation_server_basic in gcov builds
Bug#49417 some complaints about mysqld --help --verbose output
Bug#49540 DEFAULT value of binlog_format isn't the default value
Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
Bug#49644 init_connect and \0
Bug#49645 init_slave and multi-byte characters
Bug#49646 mysql --show-warnings crashes when server dies
CMakeLists.txt:
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
client/mysql.cc:
don't crash with --show-warnings when mysqld dies
config/ac-macros/plugins.m4:
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
include/my_getopt.h:
comments
include/my_pthread.h:
fix double #define
mysql-test/mysql-test-run.pl:
run sys_vars suite by default
properly recognize envirinment variables (e.g. MTR_MAX_SAVE_CORE) set to 0
escape gdb command line arguments
mysql-test/suite/sys_vars/r/rpl_init_slave_func.result:
init_slave+utf8 bug
mysql-test/suite/sys_vars/t/rpl_init_slave_func.test:
init_slave+utf8 bug
mysys/my_getopt.c:
Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
Bug#46586 When using the plugin interface the type "set" for options caused a crash.
Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
mysys/typelib.c:
support for flagset
sql/ha_ndbcluster.cc:
backport from telco tree
sql/item_func.cc:
Bug#49644 init_connect and \0
Bug#49645 init_slave and multi-byte characters
sql/sql_builtin.cc.in:
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
sql/sql_plugin.cc:
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
Bug#32902 plugin variables don't know their names
Bug#44797 plugins w/o command-line options have no disabling option in --help
sql/sys_vars.cc:
all server variables are defined here
storage/myisam/ft_parser.c:
remove unnecessary updates of param->quot
storage/myisam/ha_myisam.cc:
myisam_* variables belong here
strings/my_vsnprintf.c:
%o and %llx
unittest/mysys/my_vsnprintf-t.c:
%o and %llx tests
vio/viosocket.c:
bugfix: fix @@wait_timeout to work with socket timeouts (vs. alarm thread)
Bug#16565 mysqld --help --verbose does not order variablesBug#20413 sql_slave_skip_counter is not shown in show variables
Bug#20415 Output of mysqld --help --verbose is incomplete
Bug#25430 variable not found in SELECT @@global.ft_max_word_len;
Bug#32902 plugin variables don't know their names
Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
Bug#34829 No default value for variable and setting default does not raise error
Bug#34834 ? Is accepted as a valid sql mode
Bug#34878 Few variables have default value according to documentation but error occurs
Bug#34883 ft_boolean_syntax cant be assigned from user variable to global var.
Bug#37187 `INFORMATION_SCHEMA`.`GLOBAL_VARIABLES`: inconsistent status
Bug#40988 log_output_basic.test succeeded though syntactically false.
Bug#41010 enum-style command-line options are not honoured (maria.maria-recover fails)
Bug#42103 Setting key_buffer_size to a negative value may lead to very large allocations
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
Bug#44797 plugins w/o command-line options have no disabling option in --help
Bug#46314 string system variables don't support expressions
Bug#46470 sys_vars.max_binlog_cache_size_basic_32 is broken
Bug#46586 When using the plugin interface the type "set" for options caused a crash.
Bug#47212 Crash in DBUG_PRINT in mysqltest.cc when trying to print octal number
Bug#48758 mysqltest crashes on sys_vars.collation_server_basic in gcov builds
Bug#49417 some complaints about mysqld --help --verbose output
Bug#49540 DEFAULT value of binlog_format isn't the default value
Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
Bug#49644 init_connect and \0
Bug#49645 init_slave and multi-byte characters
Bug#49646 mysql --show-warnings crashes when server dies
The problem is a somewhat common misusage of the strmake function.
The strmake(dst, src, len) function writes at most /len/ bytes to
the string pointed to by src, not including the trailing null byte.
Hence, if /len/ is the exact length of the destination buffer, a
one byte buffer overflow can occur if the length of the source
string is equal to or greater than /len/.
client/mysqldump.c:
Make room for the trailing null byte.
libmysql/libmysql.c:
Add comment, there is enough room in the buffer.
Increase buffer length, two strings are concatenated.
libmysqld/lib_sql.cc:
Make room for the trailing null byte.
mysys/default.c:
Make room for the trailing null bytes.
mysys/mf_pack.c:
Make room for the trailing null byte.
server-tools/instance-manager/commands.cc:
Copy only if overflow isn't possible in both cases.
server-tools/instance-manager/listener.cc:
Make room for the trailing null byte.
sql/log.cc:
Make room for the trailing null byte.
sql/sp_pcontext.h:
Cosmetic fix.
sql/sql_acl.cc:
MAX_HOSTNAME already specifies space for the trailing null byte.
sql/sql_parse.cc:
Make room for the trailing null byte.
sql/sql_table.cc:
Make room for the trailing null byte.
The problem is a somewhat common misusage of the strmake function.
The strmake(dst, src, len) function writes at most /len/ bytes to
the string pointed to by src, not including the trailing null byte.
Hence, if /len/ is the exact length of the destination buffer, a
one byte buffer overflow can occur if the length of the source
string is equal to or greater than /len/.
Bug #36098 Audit plugin (wl 3771) feature disabled in 6.0
avoid recusrive locking of LOCK_plugin
include/mysql/plugin_audit.h:
fix incorrect version
sql/log.cc:
move the common code to a shared header
sql/mysqld.cc:
restore the deleted functionality
sql/set_var.cc:
remove unused parameter
sql/sql_audit.h:
two inline convenience functions
sql/sql_parse.cc:
use a simplified convenience call
sql/sql_plugin.cc:
unlock LOCK_plugin for plugin->init() call, add missing OOM check,
issue "unknown variable" error in find_sys_var, not down the stack
WL#3771
"Audit Plugin Interface"
Implement new plug-in type - AUDIT
New plug-in: audit_null
simply increments counter for how many times it was called.
include/Makefile.am:
wl3771
add new headers to distribution
include/mysql/plugin.h:
wl3771
define new AUDIT plugin type
Split out fulltext plugin type into its own header
include/mysql/plugin.h.pp:
wl3771
no real API change, just re-arranged some code
include/mysql/plugin_audit.h:
wl3771
pluggable audit interface
include/mysql/plugin_ftparser.h:
wl3771
Split out fulltext plugin type into its own header
libmysqld/CMakeLists.txt:
wl3771
add sql_audit.cc to build
libmysqld/Makefile.am:
wl3771
add sql_audit.cc to build
plugin/audit_null:
wl3771
an example plugin for testing pluggable audit interface
plugin/audit_null/Makefile.am:
wl3771
an example plugin for testing pluggable audit interface
plugin/audit_null/audit_null.c:
wl3771
an example plugin for testing pluggable audit interface
plugin/audit_null/plug.in:
wl3771
an example plugin for testing pluggable audit interface
sql/CMakeLists.txt:
wl3771
add sql_audit.cc to build
sql/Makefile.am:
wl3771
add sql_audit.cc to build
sql/event_queue.cc:
wl3771
release audit resources before waiting
sql/log.cc:
wl3771
add general audit call for log
sql/mysqld.cc:
wl3771
add audit initialize/finalize
add general audit call for error
sql/sql_audit.cc:
wl3771
pluggable audit interface implementation
sql/sql_audit.h:
wl3771
pluggable audit interface implementation
sql/sql_class.cc:
wl3771
add thd audit init/deinit calls
sql/sql_class.h:
wl3771
add required data structures for audit to THD
sql/sql_connect.cc:
wl3771
release audit resources before waiting
sql/sql_insert.cc:
wl3771
release audit plugins before waiting
sql/sql_parse.cc:
wl3771
add general audit call for results
sql/sql_plugin.cc:
wl3771
add declarations for audit plugin type
WL#3771
"Audit Plugin Interface"
Implement new plug-in type - AUDIT
New plug-in: audit_null
simply increments counter for how many times it was called.
This deadlock would occur between two connections A and B if statements
where executed in the following way:
1) Connection A executes a DML statement against table s1.t1 with
autocommit off. This causes a shared metadata lock on s1.t1 to be
acquired. (With autocommit on, the metadata lock will be dropped once
the statment completes and the deadlock will not occour.)
2) Connection B tries to DROP DATABASE s1. This will block against the
metadata lock connection A holds on s1.t1. While blocking, connection B
will hold the LOCK_mysql_create_db mutex.
3) Connection A tries to ALTER DATABASE s1. This will block when trying
to get LOCK_mysql_create_db mutex held by connection B.
4) Deadlock between DROP DATABASE and ALTER DATABASE (which has autocommit
off).
If Connection A used an explicitly started transaction rather than having
autocommit off, this deadlock did not happen as ALTER DATABASE is
disallowed inside transactions.
This patch fixes the problem by changing ALTER DATABASE to cause an
implicit commit before executing. This will cause the metadata
lock on s1.t1 to be dropped, allowing DROP DATABASE to proceed.
This will in turn cause the LOCK_mysql_create_db mutex to be unlocked,
allowing ALTER DATABASE to proceed.
Note that SQL commands other than ALTER DATABASE that also use
LOCK_mysql_create_db, already cause an implicit commit.
Incompatible change: ALTER DATABASE (and its synonym ALTER SCHEMA)
now cause an implicit commit. This must be reflected in the
documentation.
Test case added to schema.test.
sql/sql_parse.cc:
Added CF_AUTO_COMMIT_TRANS to SQLCOM_ALTER_DB.
Removed thd->active_transaction() checks from SQLCOM_DROP_DB,
SQLCOM_ALTER_DB_UPGRADE and SQLCOM_ALTER_DB as these statements
cause an implicit commit.
This deadlock would occur between two connections A and B if statements
where executed in the following way:
1) Connection A executes a DML statement against table s1.t1 with
autocommit off. This causes a shared metadata lock on s1.t1 to be
acquired. (With autocommit on, the metadata lock will be dropped once
the statment completes and the deadlock will not occour.)
2) Connection B tries to DROP DATABASE s1. This will block against the
metadata lock connection A holds on s1.t1. While blocking, connection B
will hold the LOCK_mysql_create_db mutex.
3) Connection A tries to ALTER DATABASE s1. This will block when trying
to get LOCK_mysql_create_db mutex held by connection B.
4) Deadlock between DROP DATABASE and ALTER DATABASE (which has autocommit
off).
If Connection A used an explicitly started transaction rather than having
autocommit off, this deadlock did not happen as ALTER DATABASE is
disallowed inside transactions.
This patch fixes the problem by changing ALTER DATABASE to cause an
implicit commit before executing. This will cause the metadata
lock on s1.t1 to be dropped, allowing DROP DATABASE to proceed.
This will in turn cause the LOCK_mysql_create_db mutex to be unlocked,
allowing ALTER DATABASE to proceed.
Note that SQL commands other than ALTER DATABASE that also use
LOCK_mysql_create_db, already cause an implicit commit.
Incompatible change: ALTER DATABASE (and its synonym ALTER SCHEMA)
now cause an implicit commit. This must be reflected in the
documentation.
Test case added to schema.test.
------------------------------------------------------------
2599.161.3 Ingo Struewing 2009-07-21
Bug#20667 - Truncate table fails for a write locked table
TRUNCATE TABLE was not allowed under LOCK TABLES.
The patch removes this restriction. mysql_truncate()
does now handle that case.
mysql-test/r/merge.result:
Bug#20667 - Truncate table fails for a write locked table
Updated test result.
mysql-test/r/truncate.result:
Bug#20667 - Truncate table fails for a write locked table
Updated test result.
mysql-test/r/truncate_coverage.result:
Bug#20667 - Truncate table fails for a write locked table
New test result.
mysql-test/t/merge.test:
Bug#20667 - Truncate table fails for a write locked table
Updated test case due to now working TRUNCATE under LOCK TABLES.
Added some SELECTs to show that child tables are truncated.
mysql-test/t/truncate.test:
Bug#20667 - Truncate table fails for a write locked table
Added test cases for TRUNCATE under LOCK TABLE.
mysql-test/t/truncate_coverage.test:
Bug#20667 - Truncate table fails for a write locked table
New test file. Coverage tests for TRUNCATE.
sql/sql_delete.cc:
Bug#20667 - Truncate table fails for a write locked table
Added branches for thd->locked_tables_mode.
sql/sql_parse.cc:
Bug#20667 - Truncate table fails for a write locked table
Deleted rejection of TRUNCATE in case of LOCK TABLES.
------------------------------------------------------------
2599.161.3 Ingo Struewing 2009-07-21
Bug#20667 - Truncate table fails for a write locked table
TRUNCATE TABLE was not allowed under LOCK TABLES.
The patch removes this restriction. mysql_truncate()
does now handle that case.
Bug #48210 FLUSH TABLES WITH READ LOCK deadlocks
against concurrent CREATE PROCEDURE
This deadlock occured between
a) CREATE PROCEDURE (or other commands listed below)
b) FLUSH TABLES WITH READ LOCK
If the execution of them happened in the following order:
- a) opens a table (e.g. mysql.proc)
- b) locks the global read lock (or GRL)
- a) sleeps inside wait_if_global_read_lock()
- b) increases refresh_version and sleeps waiting
for old tables to go away
Note that a) must start waiting on the GRL before FLUSH increases
refresh_version. Otherwise a) won't wait on the GRL and instead
close its tables for reopen, allowing FLUSH to complete and thus
avoid the deadlock.
With this patch the deadlock is avoided by making CREATE PROCEDURE
acquire a protection against global read locks before it starts
executing. This means that FLUSH TABLES WITH READ LOCK will have
to wait until CREATE PROCEDURE completes before acquiring the global
read lock, thereby avoiding the deadlock.
This is implemented by introducing a new SQL command flag called
CF_PROTECT_AGAINST_GRL. Commands marked with this flag will
acquire a GRL protection in the beginning of mysql_execute_command().
This patch adds the flag to CREATE, ALTER and DROP for PROCEDURE
and FUNCTION, as well as CREATE USER, DROP USER, RENAME USER and
REVOKE ALL. All these commands either call open_grant_tables() or
open_system_table_for_updated() which make them susceptible for
this deadlock.
The patch also adds the CF_PROTECT_AGAINST_GRL flag to a number
of commands that previously acquired GRL protection in their
respective SQLCOM case in mysql_execute_command().
Test case that checks for GRL protection for CREATE PROCEDURE
and CREATE USER added to mdl_sync.test.
Bug #48210 FLUSH TABLES WITH READ LOCK deadlocks
against concurrent CREATE PROCEDURE
This deadlock occured between
a) CREATE PROCEDURE (or other commands listed below)
b) FLUSH TABLES WITH READ LOCK
If the execution of them happened in the following order:
- a) opens a table (e.g. mysql.proc)
- b) locks the global read lock (or GRL)
- a) sleeps inside wait_if_global_read_lock()
- b) increases refresh_version and sleeps waiting
for old tables to go away
Note that a) must start waiting on the GRL before FLUSH increases
refresh_version. Otherwise a) won't wait on the GRL and instead
close its tables for reopen, allowing FLUSH to complete and thus
avoid the deadlock.
With this patch the deadlock is avoided by making CREATE PROCEDURE
acquire a protection against global read locks before it starts
executing. This means that FLUSH TABLES WITH READ LOCK will have
to wait until CREATE PROCEDURE completes before acquiring the global
read lock, thereby avoiding the deadlock.
This is implemented by introducing a new SQL command flag called
CF_PROTECT_AGAINST_GRL. Commands marked with this flag will
acquire a GRL protection in the beginning of mysql_execute_command().
This patch adds the flag to CREATE, ALTER and DROP for PROCEDURE
and FUNCTION, as well as CREATE USER, DROP USER, RENAME USER and
REVOKE ALL. All these commands either call open_grant_tables() or
open_system_table_for_updated() which make them susceptible for
this deadlock.
The patch also adds the CF_PROTECT_AGAINST_GRL flag to a number
of commands that previously acquired GRL protection in their
respective SQLCOM case in mysql_execute_command().
Test case that checks for GRL protection for CREATE PROCEDURE
and CREATE USER added to mdl_sync.test.
Bug#42546 Backup: RESTORE fails, thinking it finds an existing table
The problem occured when a MDL locking conflict happened for a non-existent
table between a CREATE and a INSERT statement. The code for CREATE
interpreted this lock conflict to mean that the table existed,
which meant that the statement failed when it should not have.
The problem could occur for CREATE TABLE, CREATE TABLE LIKE and
ALTER TABLE RENAME.
This patch fixes the problem for CREATE TABLE and CREATE TABLE LIKE.
It is based on code backported from the mysql-6.1-fk tree written
by Dmitry Lenev. CREATE now uses normal open_and_lock_tables() code
to acquire exclusive locks. This means that for the test case in the bug
description, CREATE will wait until INSERT completes so that it can
get the exclusive lock. This resolves the reported bug.
The patch also prohibits CREATE TABLE and CREATE TABLE LIKE under
LOCK TABLES. Note that this is an incompatible change and must
be reflected in the documentation. Affected test cases have been
updated.
mdl_sync.test contains tests for CREATE TABLE and CREATE TABLE LIKE.
Fixing the issue for ALTER TABLE RENAME is beyond the scope of this
patch. ALTER TABLE cannot be prohibited from working under LOCK TABLES
as this could seriously impact customers and a proper fix would require
a significant rewrite.
Bug#42546 Backup: RESTORE fails, thinking it finds an existing table
The problem occured when a MDL locking conflict happened for a non-existent
table between a CREATE and a INSERT statement. The code for CREATE
interpreted this lock conflict to mean that the table existed,
which meant that the statement failed when it should not have.
The problem could occur for CREATE TABLE, CREATE TABLE LIKE and
ALTER TABLE RENAME.
This patch fixes the problem for CREATE TABLE and CREATE TABLE LIKE.
It is based on code backported from the mysql-6.1-fk tree written
by Dmitry Lenev. CREATE now uses normal open_and_lock_tables() code
to acquire exclusive locks. This means that for the test case in the bug
description, CREATE will wait until INSERT completes so that it can
get the exclusive lock. This resolves the reported bug.
The patch also prohibits CREATE TABLE and CREATE TABLE LIKE under
LOCK TABLES. Note that this is an incompatible change and must
be reflected in the documentation. Affected test cases have been
updated.
mdl_sync.test contains tests for CREATE TABLE and CREATE TABLE LIKE.
Fixing the issue for ALTER TABLE RENAME is beyond the scope of this
patch. ALTER TABLE cannot be prohibited from working under LOCK TABLES
as this could seriously impact customers and a proper fix would require
a significant rewrite.
