The problem was that the server did not robustly handle a
unilateral roll back issued by the Resource Manager (RM)
due to a resource deadlock within the transaction branch.
By not acknowledging the roll back, the server (TM) would
eventually corrupt the XA transaction state and crash.
The solution is to mark the transaction as rollback-only
if the RM indicates that it rolled back its branch of the
transaction.
When running Stored Routines the Status Variable "Questions" was wrongly
incremented. According to the manual it should contain the "number of
statements that clients have sent to the server"
Introduced a new status variable 'questions' to replace the query_id
variable which currently corresponds badly with the number of statements
sent by the client.
The new behavior is ment to be backward compatible with 4.0 and at the
same time work with new features in a similar way.
This is a backport from 6.0
The '@' symbol can not be used in the host name according to rfc952.
The fix:
added function check_host_name(LEX_STRING *str)
which checks that all symbols in host name string are valid and
host name length is not more than max host name length
(just moved check_string_length() function from the parser into check_host_name()).
test_if_data_home_dir fixed to look into real path.
Checks added to mi_open for symlinks into data home directory.
per-file messages:
include/my_sys.h
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
my_is_symlink interface added
include/myisam.h
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
myisam_test_invalid_symlink interface added
myisam/mi_check.c
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
mi_open_datafile calls modified
myisam/mi_open.c
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
code added to mi_open to check for symlinks into data home directory.
mi_open_datafile now accepts 'original' file path to check if it's
an allowed symlink.
myisam/mi_static.c
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
myisam_test_invlaid_symlink defined
myisam/myisamchk.c
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
mi_open_datafile call modified
myisam/myisamdef.h
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
mi_open_datafile interface modified - 'real_path' parameter added
mysql-test/r/symlink.test
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
error codes corrected as some patch now rejected pointing inside datahome
mysql-test/r/symlink.result
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
error messages corrected in the result
mysys/my_symlink.c
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
my_is_symlink() implementsd
my_realpath() now returns the 'realpath' even if a file isn't a symlink
sql/mysql_priv.h
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
test_if_data_home_dir interface
sql/mysqld.cc
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
myisam_test_invalid_symlik set with the 'test_if_data_home_dir'
sql/sql_parse.cc
Bug#32167 another privilege bypass with DATA/INDEX DIRECTORY.
error messages corrected
test_if_data_home_dir code fixed
build)
The crash was caused by freeing the internal parser stack during the parser
execution.
This occured only for complex stored procedures, after reallocating the parser
stack using my_yyoverflow(), with the following C call stack:
- MYSQLparse()
- any rule calling sp_head::restore_lex()
- lex_end()
- x_free(lex->yacc_yyss), xfree(lex->yacc_yyvs)
The root cause is the implementation of stored procedures, which breaks the
assumption from 4.1 that there is only one LEX structure per parser call.
The solution is to separate the LEX structure into:
- attributes that represent a statement (the current LEX structure),
- attributes that relate to the syntax parser itself (Yacc_state),
so that parsing multiple statements in stored programs can create multiple
LEX structures while not changing the unique Yacc_state.
Now, Yacc_state and the existing Lex_input_stream are aggregated into
Parser_state, a structure that represent the complete state of the (Lexical +
Syntax) parser.
enabled)
Before this fix, the lexer and parser would treat the ';' character as a
different token (either ';' or END_OF_INPUT), based on convoluted logic,
which failed in simple cases where a stored procedure is implemented as a
single statement, and used in a multi query.
With this fix:
- the character ';' is always parsed as a ';' token in the lexer,
- parsing multi queries is implemented in the parser, in the 'query:' rules,
- the value of thd->client_capabilities, which is the capabilities
negotiated between the client and the server during bootstrap,
is immutable and not arbitrarily modified during parsing (which was the
root cause of the bug)
If during a FLUSH PRIVILEGES the server fails to load the new privilege
tables, the error message is lost. This patch is a back port from 5.1 which
adresses this issue by setting the server in an error state if a failure
occurrs.
This patch also corrects an incorrect variable assignment which might
cause an error state to be reverted by coincidence.
The bool data type was redefined to BOOL (4 bytes on windows).
Removed the #define and fixed some of the warnings that were uncovered
by this.
Note that the fix also disables 2 warnings :
4800 : 'type' : forcing value to bool 'true' or 'false' (performance warning)
4805: 'operation' : unsafe mix of type 'type' and type 'type' in operation
These warnings will be handled in a separate bug, as they are performance related or bogus.
Fixed to int the return type of functions that return more than
2 distinct values.
added new function test_if_data_home_dir() which checks that
path does not contain mysql data home directory.
Using of mysql data home directory in
DATA DIRECTORY & INDEX DIRECTORY is disallowed.
- Replace per-thread signal()'s with SetUnhandledExceptionFilter().
The only remaining signal() is for SIGABRT (default abort()
handler in VS2005 is broken, i.e removes user exception filter)
- remove MessageBox()'es from error handling code
- Windows port for print_stacktrace() and write_core()
- Cleanup, removed some unused functions
Here is the scenario that causes the failure.(by Mats)
1. The to-be corrupt log event (let's call it X), is split into two
packets B and C on the network level (net_write_buff()). The parts
are X = (x',x''). The part x' ends up in packet B and part x''
ends up in packet C. Prior to the corrupt event X, the event Y has
been written successfully, but has been split into two packets as
well, which we call (y',y'').
2. The master sends packet A = (y'',x') to the slave, increases the
packet sequence number, the slave receives the packet, but fails
to reply before the master gets a timeout.
3. Since the master got a timeout, it reports failure, and aborts
sending the binary log by exiting mysql_binlog_send(). However, it
leaves the buffer intact, still holding y'' (but not x', since the
write_pos is not increased).
4. After exiting mysql_binlog_send(), the master does a
disconnection of the client thread, which involves sending an
error message e to the client (i.e., the slave).
5. In this case, net_write_buff() is used again, but this time the
old contents of the packet is used so that the new packet is
D = (y'',e). Note that this will use a new packet sequence number,
since the packet number was increased in step 2.
6. The slave receives the tail y'' of the Y log event, concatenates
this with x' (which it already received), and writes the event
(x',y'') it to the relay log since it hasn't noticed anything is
amiss.
7. It then tries to read more bytes, which is either e (if the length
given for X just happened to match the length given for Y, or just
plain garbage because the slave is out of sync with what is
actually sent.
8. After a while, the SQL thread tries to execute the event (x',y''),
which is very likely to be just nonsense.
The problem can be fixed by not resetting net->error after the call of
mysql_binlog_send, so the error message will not be sent and the connection
will be closed.
When read_only option was enabled, a user without SUPER privilege could
perform CREATE DATABASE and DROP DATABASE operations.
This patch adds a check to make sure this isn't possible. It also attempts to
simplify the logic used to determine if relevant tables are updated,
making it more human readable.
FLUSH TABLES WITH READ LOCK fails to properly detect write locked
tables when running under low priority updates.
The problem is that when trying to aspire a global read lock, the
reload_acl_and_cache() function fails to properly check if the thread
has a low priority write lock, which later my cause a server crash or
deadlock.
The solution is to simple check if the thread has any type of the
possible exclusive write locks.
The root cause of the issue was that the CREATE FUNCTION grammar,
for User Defined Functions, was using the sp_name rule.
The sp_name rule is intended for fully qualified stored procedure names,
like either ident.ident, or just ident but with a default database
implicitly selected.
A UDF does not have a fully qualified name, only a name (ident), and should
not use the sp_name grammar fragment during parsing.
The fix is to re-organize the CREATE FUNCTION grammar, to better separate:
- creating UDF (no definer, can have AGGREGATE, simple ident)
- creating Stored Functions (definer, no AGGREGATE, fully qualified name)
With the test case provided, another issue was exposed which is also fixed:
the DROP FUNCTION statement was using sp_name and also failing when no database
is implicitly selected, when droping UDF functions.
The fix is also to change the grammar so that DROP FUNCTION works with
both the ident.ident syntax (to drop a stored function), or just the ident
syntax (to drop either a UDF or a Stored Function, in the current database)
similar to bug_27716, but it was stressed on in the synopsis on that there is another
side of the artifact affecting behaviour in transaction.
Fixed with deploying multi_delete::send_error() - otherwise never called - and refining its logic
to perform binlogging job if needed.
The changeset includes the following side effects:
- added tests to check bug_23333's scenarios on the mixture of tables for multi_update;
- fixes bug@30763 with two-liner patch and a test coinciding to one added for bug_23333.
active_mi has been reset (shutdown) at the time of quering with
SHOW SLAVE STATUS so that
at handling of SHOW an attempt to read its members segfaults.
Fixed with checking the value of active_mi before to call show_master_info()
Merely send_ok() is invoked when active_mi does not exist.
A test can not be easiely written.
Notice, there are more analogical cases in the code which require a similar
treatment (to be reported as a bug separately).
The problem was that aborted_threads variable was updated
twice when a client connection had been aborted.
The fix is to refactor a code to have aborted_threads updated
only in one place.
When dumping database from a 4.x server, the mysqldump client
inserted a delimiter sign inside special commentaries of the form:
/*!... CREATE DATABASE IF NOT EXISTS ... ;*/
During restoration that dump file was splitten by delimiter signs on
the client side, and the rest of some commentary strings was prepended
to following statements.
The 4x_server_emul test case option has been added for use with the
DBUG_EXECUTE_IF debugging macro. This option affects debug server
builds only to emulate particular behavior of a 4.x server for
the mysqldump client testing. Non-debugging builds are not affected.
The SELECT query with more than 31 nested dependent SELECT queries returned
wrong result.
New error message has been added: ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT.
It will be reported as: "Too high level of nesting for select".
Problem: thd->thread_specific_used flag is not set executing a statement
containig connection_id() function using PS protocol, that leads to
improper binlog event creation.
Fix: set the flag in the Item_func_connection_id::fix_fields().
Bug #27417 thd->no_trans_update.stmt lost value inside of SF-exec-stack
Once had been set the flag might later got reset inside of a stored routine
execution stack.
The reason was in that there was no check if a new statement started at time
of resetting.
The artifact affects most of binlogable DML queries. Notice, that multi-update
is wrapped up within
bug@27716 fix, multi-delete bug@29136.
Fixed with saving parent's statement flag of whether the statement modified
non-transactional table, and unioning (merging) the value with that was gained
in mysql_execute_command.
Resettling thd->no_trans_update members into thd->transaction.`member`;
Asserting code;
Effectively the following properties are held.
1. At the end of a substatement thd->transaction.stmt.modified_non_trans_table
reflects the fact if such a table got modified by the substatement.
That also respects THD::really_abort_on_warnin() requirements.
2. Eventually thd->transaction.stmt.modified_non_trans_table will be computed as
the union of the values of all invoked sub-statements.
That fixes this bug#27417;
Computing of thd->transaction.all.modified_non_trans_table is refined to base to
the stmt's value for all the case including insert .. select statement which
before the patch had an extra issue bug@28960.
Minor issues are covered with mysql_load, mysql_delete, and binloggin of insert in
to temp_table select.
The supplied test verifies limitely, mostly asserts. The ultimate testing is defered
for bug@13270, bug@23333.
causes full table lock on innodb table.
Also fixes Bug#28502 Triggers that update another innodb table
will block on X lock unnecessarily (duplciate).
Code review fixes.
Both bugs' synopses are misleading: InnoDB table is
not X locked. The statements, however, cannot proceed concurrently,
but this happens due to lock conflicts for tables used in triggers,
not for the InnoDB table.
If a user had an InnoDB table, and two triggers, AFTER UPDATE and
AFTER INSERT, competing for different resources (e.g. two distinct
MyISAM tables), then these two triggers would not be able to execute
concurrently. Moreover, INSERTS/UPDATES of the InnoDB table would
not be able to run concurrently.
The problem had other side-effects (see respective bug reports).
This behavior was a consequence of a shortcoming of the pre-locking
algorithm, which would not distinguish between different DML operations
(e.g. INSERT and DELETE) and pre-lock all the tables
that are used by any trigger defined on the subject table.
The idea of the fix is to extend the pre-locking algorithm to keep track,
for each table, what DML operation it is used for and not
load triggers that are known to never be fired.
Problem: logging queries not using indexes we check a special flag which
is set only at the server startup and is not changing with a corresponding
server variable together.
Fix: check the variable value instead of the flag.
fails if a database is not selected prior.
The problem manifested itself when a user tried to
create a routine that had non-fully-qualified identifiers in its bodies
and there was no current database selected.
This is a regression introduced by the fix for Bug 19022:
The patch for Bug 19022 changes the code to always produce a warning
if we can't resolve the current database in the parser.
In this case this was not necessary, since even though the produced
parsed tree was incorrect, we never re-use sphead
that was obtained at first parsing of CREATE PROCEDURE.
The sphead that is anyhow used is always obtained through db_load_routine,
and there we change the current database to sphead->m_db before
calling yyparse.
The idea of the fix is to resolve the current database directly using
lex->sphead->m_db member when parsing a stored routine body, when
such is present.
This patch removes the need to reset the current database
when loading a trigger or routine definition into SP cache.
The redundant code will be removed in 5.1.
LOCK TABLES takes a list of tables to lock. It may lock several
tables successfully and then encounter a tables that it can't lock,
e.g. because it's locked. In such case it needs to undo the locks on
the already locked tables. And it does that. But it has also notified
the relevant table storage engine handlers that they should lock.
The only reliable way to ensure that the table handlers will give up
their locks is to end the transaction. This is what UNLOCK TABLE
does : it ends the transaction if there were locked tables by LOCK
tables.
It is possible to end the transaction when the lock fails in
LOCK TABLES because LOCK TABLES ends the transaction at its start
already.
Fixed by ending (again) the transaction when LOCK TABLES fails to
lock a table.