This crash occured if the same debug trace file was closed twice,
leading to the same memory being free'd twice. This could occur
if the "debug" server system variable refered to the same trace
file in both global and session scope.
Example of an order of events that would lead to a crash:
1) Enable debug tracing to a trace file (global scope)
2) Enable debug tracing to the same trace file (session scope)
3) Reset debug settings (global scope)
4) Reset debug settings (session scope)
This caused a crash because the trace file was, by mistake, closed
in 3), leading to the same memory being free'd twice when the file
was closed again in 4).
Internally, the debug settings are stored in a stack, with session
settings (if any) on top and the global settings below. Each connection
has its own stack. When a set of settings is changed, it must be
determined if its debug trace file is to be closed. Before, this was done
by only checking below on the settings stack. So if the global settings
were changed, an existing debug trace file reference in session settings
would be missed. This caused the file to be closed even if it was in use,
leading to a crash later when it was closed again.
This patch fixes the problem by preventing the trace file from being shared
between global and session settings. If session debug settings are set without
specifying a new trace file, stderr is used for output. This is a change
in behaviour and should be reflected in the documentation.
Test case added to variables.test.
This patch implements I_S.PLUGINS.LOAD_OPTION column
as specified by WL#5496.
mysql-test/r/plugin_load_option.result:
A test case for WL#5496.
mysql-test/suite/funcs_1/r/is_columns_is.result:
Adjusted a test case according to WL#5496.
mysql-test/t/plugin_load_option.test:
A test case for WL#5496.
sql/sql_show.cc:
Added LOAD_OPTION column to I_S.PLUGINS.
This patch implements "permanent" load option for
plugins as specified by WL#5341.
mysql-test/r/plugin_load_option.result:
A test case for WL#5341.
mysql-test/t/plugin_load_option-master.opt:
A test case for WL#5341.
mysql-test/t/plugin_load_option.test:
A test case for WL#5341.
sql/share/errmsg-utf8.txt:
An error message for WL#5341.
sql/sql_plugin.cc:
Added FORCE_PLUS_PERMANENT plugin load option.
sql/sql_plugin.h:
Expose and use plugin load option instead of
is_mandatory flag. This is a requirement for
to-be-implemented WL5496.
In case of outer join and emtpy WHERE conditon
'always true' condition is created for WHERE clasue.
Later in mysql_select() original SELECT_LEX WHERE
condition is overwritten with created cond.
However SELECT_LEX condition is also used as inital
condition in mysql_select()->JOIN::prepare().
On second execution of PS modified SELECT_LEX condition
is taken and it leads to crash.
The fix is to restore original SELECT_LEX condition
(set to NULL if original cond is NULL) in
reinit_stmt_before_use().
HAVING clause is fixed too for safety reason
(no test case as I did not manage to think out
appropriate example).
mysql-test/r/ps.result:
test case
mysql-test/t/ps.test:
test case
sql/sql_prepare.cc:
restore original SELECT_LEX condition
(set to NULL if original cond is NULL) in
reinit_stmt_before_use()
Fixed a number of memory leaks discovered by valgrind.
dbug/dbug.c:
This is actually an addendum to the fix for bug #52629:
- there is no point in limiting the fix to just global
variables, session ones are also affected.
- zero all fields when allocating a new 'state' structure so
that FreeState() does not deal with unitialized data later.
- add a check for a NULL pointer in DBUGCloseFile()
mysql-test/r/partition_error.result:
Added a test case for bug #56709.
mysql-test/r/variables_debug.result:
Added a test case for bug #56709.
mysql-test/t/partition_error.test:
Added a test case for bug #56709.
mysql-test/t/variables_debug.test:
Added a test case for bug #56709.
sql/item_timefunc.cc:
There is no point in declaring 'value' as a member of
Item_extract and dynamically allocating memory for it in
Item_extract::fix_length_and_dec(), since this string is only
used as a temporary storage in Item_extract::val_int().
sql/item_timefunc.h:
Removed 'value' from the Item_extract class definition.
sql/sql_load.cc:
- we may need to deallocate 'buffer' even when 'error' is
non-zero in some cases, since 'error' is public, and there is
external code modifying it.
- assign NULL to buffer when deallocating it so that we don't
do it twice in the destructor
- there is no point in changing 'error' in the destructor.
Added --enable-connect-log, somewhet similar to --enable-query-log
If query log is disabled, disable connect log too
Also some related cleanup in mysqltest.test: removing duplicate test loop
REPAIR of merge table
Bug #56422 CHECK TABLE run when the table is locked reports
corruption along with timeout
The crash happened if a table maintenance statement (ANALYZE TABLE,
REPAIR TABLE, etc.) was executed on a MERGE table and opening and
locking a child table failed. This could for example happen if a child
table did not exist or if a lock timeout happened while waiting for
a conflicting metadata lock to disappear.
Since opening and locking the MERGE table and its children failed,
the tables would be closed and the metadata locks released.
However, TABLE_LIST::table for the MERGE table would still be set,
with its value invalid since the tables had been closed.
This caused the table maintenance statement to try to continue
and upgrade the metadata lock on the MERGE table. But since the lock
already had been released, this caused a segfault.
This patch fixes the problem by setting TABLE_LIST::table to NULL
if open_and_lock_tables() fails. This prevents maintenance
statements from continuing and trying to upgrade the metadata lock.
The patch includes a 5.5 version of the fix for
Bug #46339 crash on REPAIR TABLE merge table USE_FRM.
This bug caused REPAIR TABLE ... USE_FRM to give an assert
when used on merge tables.
The patch also enables the CHECK TABLE statement for log tables.
Before, CHECK TABLE for log tables gave ER_CANT_LOCK_LOG_TABLE,
yet still counted the statement as successfully executed.
With the changes to table maintenance statement error handling
in this patch, CHECK TABLE would no longer be considered as
successful in this case. This would have caused upgrade scripts
to mistakenly think that the general and slow logs are corrupted
and have to be repaired. Enabling CHECK TABLES for log tables
prevents this from happening.
Finally, the patch changes the error message from "Corrupt" to
"Operation failed" for a number of issues not related to table
corruption. For example "Lock wait timeout exceeded" and
"Deadlock found trying to get lock".
Test cases added to merge.test and check.test.
Fixed incorrect handling of user credentials when authenticating
via proxy user. Now the server will use the proxies user's
access mask and host to update the security context runtime
structure when logging in.
Fixed a compilation warning with the embedded library.
Fixed a crash when doing a second GRANT PROXY on ''@'' due to
incomplete equality check logic.
tree for embedded server
Test case for bug #56251 "Deadlock with INSERT
DELAYED and MERGE tables" can't be run against
embedded server. Embedded server converts all
DELAYED INSERTs into ordinary INSERTs and this
test can't work properly if such conversion
happens.
Moved this test from merge.test to delayed.test
which is skipped if test suite is run with
--embedded-server option.
The problem was that RENAME TABLE caused an assert if the system variable
lower_case_table_names was 2 (default on Mac OS X) and the old table name
was given in upper case. This caused lowercase_table2.test to fail.
The assert checks that an exclusive metadata lock is held by the connection
trying to do RENAME TABLE - specificially during updates of table triggers.
The assert was triggered since the check is case sensitive and the lock
was held on the normalized (lower case) version of the table name.
This patch fixes the problem by making sure a normalized version of the
table name is used for the metadata lock check, while using a non-normalized
version of the table name for the rename of trigger files. The same is done
for ALTER TABLE ... RENAME.
Regression testing for the bug itself is already covered by
lowercase_table2.test. Additional coverage added to lowercase_fs_off.test.
When having a sub query in partitioned innodb one could
make the partitioning engine to search for a 'index_next_same'
on a partition that had not been initialized.
Problem was that the subselect function looks at table->status
which was not set in the partitioning handler when it skipped
scanning due to no matching partitions found.
Fixed by setting table->status = STATUS_NOT_FOUND when
there was no partitions to scan. (If there are partitions to
scan, it will be set in the partitions handler.)
mysql-test/r/partition_innodb.result:
added result
mysql-test/t/partition_innodb.test:
added test
sql/ha_partition.cc:
set table status to not found, if there ar no partitions to scan.
tables".
Attempting to issue an INSERT DELAYED statement for a MERGE
table might have caused a deadlock if it happened as part of
a transaction or under LOCK TABLES, and there was a concurrent
DDL or LOCK TABLES ... WRITE statement which tried to lock one
of its underlying tables.
The problem occurred when a delayed insert handler thread tried
to open a MERGE table and discovered that to do this it had also
to open all underlying tables and hence acquire metadata
locks on them. Since metadata locks on the underlying tables were
not pre-acquired by the connection thread executing INSERT DELAYED,
attempts to do so might lead to waiting. In this case the
connection thread had to wait for the delayed insert thread.
If the thread which was preventing the lock on the underlying table
from being acquired had to wait for the connection thread (due to
this or other metadata locks), a deadlock occurred.
This deadlock was not detected by the MDL deadlock detector since
waiting for the handler thread by the connection thread is not
represented in the wait-for graph.
This patch solves the problem by ensuring that the delayed
insert handler thread never tries to open underlying tables
of a MERGE table. Instead open_tables() is aborted right after
the parent table is opened and a ER_DELAYED_NOT_SUPPORTED
error is emitted (which is passed to the connection thread and
ultimately to the user).
mysql-test/r/merge.result:
Added test for bug #56251 "Deadlock with INSERT DELAYED and
MERGE tables".
mysql-test/t/merge.test:
Added test for bug #56251 "Deadlock with INSERT DELAYED and
MERGE tables".
sql/sql_base.cc:
Changed open_n_lock_single_table() to take prelocking strategy
as an argument instead of always using DML_prelocking_strategy.
sql/sql_base.h:
Changed open_n_lock_single_table() to take prelocking strategy
as an argument instead of always using DML_prelocking_strategy.
Added a version of this function which is compatible with old
signature.
sql/sql_insert.cc:
When opening MERGE table in delayed insert thread stop and emit
ER_DELAYED_NOT_SUPPORTED right after opening main table and
before opening underlying tables. This ensures that we won't
try to acquire metadata lock on underlying tables which might
lead to a deadlock.
This is achieved by using special prelocking strategy which
abort open_tables() process as soon as we discover that we
have opened table with engine which doesn't support delayed
inserts.
ORDER BY computed col
GROUP BY implies ORDER BY in the MySQL dialect of SQL. Therefore, when an
index on the first table in the query is used, and that index satisfies
ordering according to the GROUP BY clause, the query optimizer estimates the
number of tuples that need to be read from this index. If there is a LIMIT
clause, table statistics on tables following this 'sort table' are employed.
There may be a separate ORDER BY clause however, which mandates reading the
whole 'sort table' anyway. But the previous estimate was left untouched.
Fixed by removing the estimate from EXPLAIN output if GROUP BY is used in
conjunction with an ORDER BY clause that mandates using a temporary table.
The problem was that issuing XA END when the XA transaction was
already ended, caused an assertion. This assertion tests that
the server does not try to send OK to the client if there has
already been an error reported. The bug was only noticeable on
debug versions of the server.
The reason for the problem was that the trans_xa_end() function
reported success if the transaction was at XA_IDLE state at the
end regardless of any errors occured during processing of
trans_xa_end(). So if the transaction state was XA_IDLE already,
reported errors would be ignored.
This patch fixes the problem by having trans_xa_end() take into
consideration any reported errors. The patch also fixes a similar
bug with XA PREPARE.
Test case added to xa.test.
Version "5.1.42 SUSE MySQL RPM"
When a query was using a DATE or DATETIME value formatted
using different formatting than "yyyy-mm-dd HH:MM:SS", a
query with a greater-or-equal '>=' condition matched only
greater values in an indexed TIMESTAMP column.
The problem was introduced by the fix for the bug 46362
and partially solved (for DATE and DATETIME columns only)
by the fix for the bug 47925.
The stored_field_cmp_to_item function has been modified
to take into account TIMESTAMP columns like we do for
DATE and DATETIME columns.
mysql-test/r/type_timestamp.result:
Test case for bug #55779.
mysql-test/t/type_timestamp.test:
Test case for bug #55779.
sql/item.cc:
Bug #55779: select does not work properly in mysql server
Version "5.1.42 SUSE MySQL RPM"
The stored_field_cmp_to_item function has been modified
to take into account TIMESTAMP columns like we do for
DATE and DATETIME.
to 5.5 (removed one test case as it is no longer valid).
mysql-test/r/select.result:
Removed a part of the test case for bug#48291 since it is not
valid anymore. The comments for the removed part were actually
describing a side-effect from the problem addressed by the
addendum patch for bug #54190.
mysql-test/t/select.test:
Removed a part of the test case for bug#48291 since it is not
valid anymore. The comments for the removed part were actually
describing a side-effect from the problem addressed by the
addendum patch for bug #54190.
table causes assert failure".
Attempting to use FLUSH TABLE table_list WITH READ LOCK
statement for a MERGE table led to an assertion failure if
one of its children was not present in the list of tables
to be flushed. The problem was not visible in non-debug builds.
The assertion failure was caused by the fact that in such
situations FLUSH TABLES table_list WITH READ LOCK implementation
tried to use (e.g. lock) such child tables without acquiring
metadata lock on them. This happened because when opening tables
we assumed metadata locks on all tables were already acquired
earlier during statement execution and a such assumption was
false for MERGE children.
This patch fixes the problem by ensuring at open_tables() time
that we try to acquire metadata locks on all tables to be opened.
For normal tables such requests are satisfied instantly since
locks are already acquired for them. For MERGE children metadata
locks are acquired in normal fashion.
Note that FLUSH TABLES merge_table WITH READ LOCK will lock for
read both the MERGE table and its children but will flush only
the MERGE table. To flush children one has to mention them in table
list explicitly. This is expected behavior and it is consistent with
usage patterns for this statement (e.g. in mysqlhotcopy script).
mysql-test/r/flush.result:
Added test case for bug #55273 "FLUSH TABLE tm WITH READ LOCK
for Merge table causes assert failure".
mysql-test/t/flush.test:
Added test case for bug #55273 "FLUSH TABLE tm WITH READ LOCK
for Merge table causes assert failure".
sql/sql_base.cc:
Changed lock_table_names() to support newly introduced
MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag.
sql/sql_base.h:
Introduced MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag for
open_tables() and lock_table_names() which allows to skip
acquiring of global and schema-scope locks when SNW, SNRW or
X metadata locks are acquired.
sql/sql_reload.cc:
Changed "FLUSH TABLES table_list WITH READ LOCK" code not to
cause assert about missing metadata locks when MERGE table is
flushed without one of its underlying tables.
To achieve this we no longer call open_and_lock_tables() with
MYSQL_OPEN_HAS_MDL_LOCK flag so this function automatically
acquires metadata locks on MERGE children if such lock has
not been already acquired at earlier stage. Instead we call
this function with MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag to
suppress acquiring of global IX lock in order to keep FLUSH
TABLES table_list WITH READ LOCK compatible with FLUSH TABLE
WITH READ LOCK.
Also changed implementation to use lock_table_names() function
for pre-acquiring of metadata locks instead of custom code.
To implement this change moved setting of open_type member for
table list elements to parser.
sql/sql_yacc.yy:
Now we set acceptable type of table for FLUSH TABLES table_list
WITH READ LOCK at parsing time instead of execution time.
result
Row subqueries producing no rows were not handled as UNKNOWN
values in row comparison expressions.
That was a result of the following two problems:
1. Item_singlerow_subselect did not mark the resulting row
value as NULL/UNKNOWN when no rows were produced.
2. Arg_comparator::compare_row() did not take into account that
a whole argument may be NULL rather than just individual scalar
values.
Before bug#34384 was fixed, the above problems were hidden
because an uninitialized (i.e. without any stored value) cached
object would appear as NULL for scalar values in a row subquery
returning an empty result. After the fix
Arg_comparator::compare_row() would try to evaluate
uninitialized cached objects.
Fixed by removing the aforementioned problems.
mysql-test/r/row.result:
Added a test case for bug #54190.
mysql-test/r/subselect.result:
Updated the result for a test relying on wrong behavior.
mysql-test/t/row.test:
Added a test case for bug #54190.
sql/item_cmpfunc.cc:
If either of the argument rows is NULL, return NULL as the
result of comparison.
sql/item_subselect.cc:
Adjust null_value for Item_singlerow_subselect depending on
whether a row has been produced by the row subquery.
ALTER TABLE on a MERGE table could cause a deadlock with two
other connections if we reached a situation where:
1) A connection doing ALTER TABLE can't upgrade to MDL_EXCLUSIVE on the
parent table, but holds TL_READ_NO_INSERT on the child tables.
2) A connection doing DELETE on a child table can't get TL_WRITE on it
since ALTER TABLE holds TL_READ_NO_INSERT.
3) A connection doing SELECT on the parent table can't get TL_READ on
the child tables since TL_WRITE is ahead in the lock queue, but holds
MDL_SHARED_READ on the parent table preventing ALTER TABLE from upgrading.
For regular tables, this deadlock is avoided by having ALTER TABLE
take a MDL_SHARED_NO_WRITE metadata lock on the table. This prevents
DELETE from acquiring MDL_SHARED_WRITE on the table before ALTER TABLE
tries to upgrade to MDL_EXCLUSIVE. In the example above, SELECT would
therefore not be blocked by the pending DELETE as DELETE would not be
able to enter TL_WRITE in the table lock queue.
This patch fixes the problem for merge tables by using the same metadata
lock type for child tables as for the parent table. The child tables will
in this case therefore be locked with MDL_SHARED_NO_WRITE, preventing
DELETE from acquiring a metadata lock and enter into the table lock queue.
Change in behavior: By taking the same metadata lock for child tables
as for the parent table, LOCK TABLE on the parent table will now also
implicitly lock the child tables. Since LOCK TABLE on the parent table
now takes more than one metadata lock, it is possible for LOCK TABLE
... WRITE on the parent table or child tables to give ER_LOCK_DEADLOCK
error.
Test case added to mdl_sync.test.
Merge.test/.result has been updated to reflect the change to LOCK TABLE.
