The problem is that the internal variable used to specify a
transaction with consistent read was being used outside the
processing context of a START TRANSACTION WITH CONSISTENT
SNAPSHOT statement. The practical consequence was that a
consistent snapshot specification could leak to unrelated
transactions on the same session.
The solution is to ensure a consistent snapshot clause is
only relied upon for the START TRANSACTION statement.
This is already fixed in a similar way on 6.0.
The problem is that a SELECT .. FOR UPDATE statement might open
a table and later wait for a impeding global read lock without
noticing whether it is holding a table that is being waited upon
the the flush phase of the process that took the global read
lock.
The same problem also affected the following statements:
LOCK TABLES .. WRITE
UPDATE .. SET (update and multi-table update)
TRUNCATE TABLE ..
LOAD DATA ..
The solution is to make the above statements wait for a impending
global read lock before opening the tables. If there is no
impending global read lock, the statement raises a temporary
protection against global read locks and progresses smoothly
towards completion.
Important notice: the patch does not try to address all possible
cases, only those which are common and can be fixed unintrusively
enough for 5.0.
due to name_const substitution
Problem:
"In general, statements executed within a stored procedure
are written to the binary log using the same rules that
would apply were the statements to be executed in standalone
fashion. Some special care is taken when logging procedure
statements because statement execution within procedures
is not quite the same as in non-procedure context".
For example, each reference to a local variable in SP's
statements is replaced by NAME_CONST(var_name, var_value).
Queries like
"CREATE TABLE ... SELECT FUNC(local_var ..."
are logged as
"CREATE TABLE ... SELECT FUNC(NAME_CONST("local_var", var_value) ..."
that leads to differrent field names and
might result in "Incorrect column name" if var_value is long enough.
Fix: in 5.x we'll issue a warning in such a case.
In 6.0 we should get rid of NAME_CONST().
Note: this issue and change should be described in the documentation
("Binary Logging of Stored Programs").
Fine-tuning. Broke out comparison into method by
suggestion of Davi. Clarified comments. Reverting
test-case which I find too brittle; proper test
case in 5.1+.
(Pushing for Azundris)
We allow security-contexts with NULL users (for
system-threads and for unauthenticated users).
If a non-SUPER-user tried to KILL such a thread,
we tried to compare the user-fields to see whether
they owned that thread. Comparing against NULL was
not a good idea.
If KILLer does not have SUPER-privilege, we
specifically check whether both KILLer and KILLee
have a non-NULL user before testing for string-
equality. If either is NULL, we reject the KILL.
mysql.procs_priv table itself does not get replicated.
Inserting routine privilege record into mysql.procs_priv table
is triggered by creating function/procedure statements
according to current user's privileges.
Because the current user of SQL thread has GLOBAL_ACL,
which doesn't need any check mysql.procs_priv privilege
when create/alter/execute routines.
Corresponding GLOBAL_ACL privilege user
doesn't insert routine privilege record into
mysql.procs_priv when creating a routine.
Fixed by switching the current user of SQL thread to definer user if
the definer user exists on slave.
That populates procs_priv, otherwise to keep the SQL thread
user and procs_priv remains unchanged.
An unnecessarily restrictive lock were taken on sub-SELECTs during DELETE.
During parsing, a global structure is reused for sub-SELECTs and the attribute
keeping track of lock options were not reset properly.
This patch introduces a new attribute to keep track on the syntactical lock
option elements found in a sub-SELECT and then sets the lock options accordingly.
Now the sub-SELECTs will try to acquire a READ lock if possible
instead of a WRITE lock as inherited from the outer DELETE statement.
- Remove bothersome warning messages. This change focuses on the warnings
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length
There is an inconsistency with DROP DATABASE IF EXISTS, DROP
TABLE IF EXISTS and DROP VIEW IF EXISTS: those are binlogged even
if the DB or TABLE does not exist, whereas DROP PROCEDURE IF
EXISTS does not. It would be nice or at least consistent if DROP
PROCEDURE/STATEMENT worked the same too.
Fixed DROP PROCEDURE|FUNCTION IF EXISTS by adding a call to
write_bin_log in mysql_execute_command. Checked also if all
documented "DROP (...) IF EXISTS" get binlogged. Left out DROP
SERVER IF EXISTS because it seems that it only gets binlogged when
using row event (see BUG#25705).
code backported from 6.0
per-file messages:
include/my_global.h
Remove SC_MAXWIDTH. This is unused and irrelevant nowadays.
include/my_sys.h
Remove errbuf declaration and unused definitions.
mysys/my_error.c
Remove errbuf definition and move and adjust ERRMSGSIZE.
mysys/my_init.c
Declare buffer on the stack and use my_snprintf.
mysys/safemalloc.c
Use size explicitly. It's more than enough for the message at hand.
sql/sql_error.cc
Use size explicitly. It's more than enough for the message at hand.
sql/sql_parse.cc
Declare buffer on the stack. Use my_snprintf as it will result in
less stack space being used than by a system provided sprintf --
this allows us to put the buffer on the stack without causing much
trouble. Also, the use of errbuff here was not thread-safe as the
function can be entered concurrently from multiple threads.
sql/sql_table.cc
Use MYSQL_ERRMSG_SIZE. Extra space is not needed as my_snprintf will
nul terminate strings.
storage/myisam/ha_myisam.cc
Use MYSQL_ERRMSG_SIZE.
sql/share/errmsg.txt
Error message truncation in test "innodb" in embedded mode
filename in the error message can safely take up to 210 symbols.
If the system time is adjusted back during a query execution
(resulting in the end time being earlier than the start time)
the code that prints to the slow query log gets confused and
prints unsigned negative numbers.
Fixed by not logging the statements that would have negative
execution time due to time shifts.
No test case since this would involve changing the system time.
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.
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 failure was caused by executing a CREATE-SELECT statement that creates a
table in another database than the current one. In row-based logging, the
CREATE statement was written to the binary log without the database, hence
creating the table in the wrong database, causing the following inserts to
fail since the table didn't exist in the given database.
Fixed the bug by adding a parameter to store_create_info() that will make
the function print the database name before the table name and used that
in the calls that write the CREATE statement to the binary log. The database
name is only printed if it is different than the currently selected database.
The output of SHOW CREATE TABLE has not changed and is still printed without
the database name.
warnings)
Before this fix, several places in the code would raise a warning with an
error code 0, making it impossible for a stored procedure, a connector,
or a client application to trigger logic to handle the warning.
Also, the warning text was hard coded, and therefore not translated.
With this fix, new errors numbers have been created to represent these
warnings, and the warning text is coded in the errmsg.txt file.
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()).
The problem is that when statement-based replication was enabled,
statements such as INSERT INTO .. SELECT FROM .. and CREATE TABLE
.. SELECT FROM need to grab a read lock on the source table that
does not permit concurrent inserts, which would in turn be denied
if the source table is a log table because log tables can't be
locked exclusively.
The solution is to not take such a lock when the source table is
a log table as it is unsafe to replicate log tables under statement
based replication. Furthermore, the read lock that does not permits
concurrent inserts is now only taken if statement-based replication
is enabled and if the source table is not a log table.
statement/stored procedure
View privileges are properly checked after the fix for bug no
36086, so the method TABLE_LIST::get_db_name() must be used
instead of field TABLE_LIST::db, as this only works for tables.
Bug appears when accessing views in prepared statements.
The check_table_access function initializes per-table grant info and performs
access rights check. It wasn't called for SHOW STATUS statement thus left
grants info uninitialized. In some cases this led to server crash. In other
cases it allowed a user to check for presence/absence of arbitrary values in
any tables.
Now the check_table_access function is called prior to the statement
processing.
This patch also fixes bugs 36963 and 35600.
- In many places a view was confused with an anonymous derived
table, i.e. access checking was skipped. Fixed by introducing a
predicate to tell the difference between named and anonymous
derived tables.
- When inserting fields for "SELECT * ", there was no
distinction between base tables and views, where one should be
made. View privileges are checked elsewhere.
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
Fix for a valgrind warning due to a jump on a uninitialized
variable. The problem was that the sql profile preparation
function wasn't being called for all possible code paths
of query execution.
The solution is to ensure that query profiling is always
started before dispatch_command function is called and to
explicitly call the profile preparation function on bootstrap.
