ISSUE: Heap corruption occurs and hence mysql server
terminates abnormally in String variable destructor
when ZEROFILL is used for a column.
Though the abnormal termination is observed in the
String destructor, heap corruption occurs at earlier
stage when function Field_num::prepend_zeros() is called.
This function, prepends zeros to the actual data and
works on entire field length. Since the allocated memory
could be less than the field length, heap corruption occurs.
Later, when String destructor tries to free heap, the server
terminates abnormally since the heap is corrupt.
SOLUTION: In Field_num::prepend_zeros() function, if allocated memory
is less than the field length, re-allocate memory enough to
hold field length size data.
That is, when the precision of DEFAULT NOW() is less than
the precision of the column, do not convert it to unireg_check,
use the new approach where DEFAULT is tryly an expression.
* revert part of the db7edfe that moved calculations from
fix_fields to val_str for Item_func_sysconst and descendants
* mark session state dependent functions in check_vcol_func_processor()
* re-run fix_fields for all such functions for every statement
* fix CURRENT_USER/CURRENT_ROLE not to use Name_resolution_context
(that is allocated on the stack in unpack_vcol_info_from_frm())
Note that NOW(), CURDATE(), etc use lazy initialization and do *not*
force fix_fields to be re-run. The rule is:
* lazy initialization is *not* allowed, if it changes metadata (so,
e.g. DAYNAME() cannot use it)
* lazy initialization is *preferrable* if it has side effects (e.g.
NOW() sets thd->time_zone_used=1, so it's better to do it when
the value of NOW is actually needed, not when NOW is simply prepared)
ISSUE: Queries with mediumint as column when operated with
long long type of data results in buffer overflow in
store_long function.
The merging rule specified for (MYSQL_TYPE_LONGLONG
MYSQL_TYPE_INT24) is MYSQL_TYPE_LONG. Due to this store_long
function was getting called which resulted in buffer overflow.
SOLUTION:
The correct merging rule for (MYSQL_TYPE_LONGLONG,
MYSQL_TYPE_INT24) should be MYSQL_TYPE_LONGLONG.
So, instead of function store_long, function store_longlong
is called which correctly handles the type MYSQL_TYPE_LONGLONG.
External Bug #23645238 is a duplicate of this issue.
Adding Converter_double_to_longlong and reusing it in:
1. Field_longlong::store(double nr)
2. Field_double::val_int()
3. Item::val_int_from_real()
4. Item_dyncol_get::val_int()
As a good side efferct, now overflow in conversion in the mentioned
val_xxx() methods return exactly the same warning.
* remove a confusing method name - Field::set_default_expression()
* remove handler::register_columns_for_write()
* rename stuff
* add asserts
* remove unlikely unlikely
* remove redundant if() conditions
* fix mark_unsupported_function() to report the most important violation
* don't scan vfield list for default values (vfields don't have defaults)
* move handling for DROP CONSTRAINT IF EXIST where it belongs
* don't protect engines from Alter_inplace_info::ALTER_ADD_CONSTRAINT
* comments
- Force usage of () around complex DEFAULT expressions
- Give error if DEFAULT expression contains invalid characters
- Don't use const_charset_conversion for stored Item_func_sysconf expressions
as the result is not constaint over different executions
- Fixed Item_func_user() to not store calculated value in str_value
MDEV-10134 Add full support for DEFAULT
- Added support for using tables with MySQL 5.7 virtual fields,
including MySQL 5.7 syntax
- Better error messages also for old cases
- CREATE ... SELECT now also updates timestamp columns
- Blob can now have default values
- Added new system variable "check_constraint_checks", to turn of
CHECK constraint checking if needed.
- Removed some engine independent tests in suite vcol to only test myisam
- Moved some tests from 'include' to 't'. Should some day be done for all tests.
- FRM version increased to 11 if one uses virtual fields or constraints
- Changed to use a bitmap to check if a field has got a value, instead of
setting HAS_EXPLICIT_VALUE bit in field flags
- Expressions can now be up to 65K in total
- Ensure we are not refering to uninitialized fields when handling virtual fields or defaults
- Changed check_vcol_func_processor() to return a bitmap of used types
- Had to change some functions that calculated cached value in fix_fields to do
this in val() or getdate() instead.
- store_now_in_TIME() now takes a THD argument
- fill_record() now updates default values
- Add a lookahead for NOT NULL, to be able to handle DEFAULT 1+1 NOT NULL
- Automatically generate a name for constraints that doesn't have a name
- Added support for ALTER TABLE DROP CONSTRAINT
- Ensure that partition functions register virtual fields used. This fixes
some bugs when using virtual fields in a partitioning function
use Item->neg to convert generate negative Item_num's
instead of Item_func_neg(Item_num).
Based on the following commit:
Author: Monty <monty@mariadb.org>
Date: Mon May 30 22:44:00 2016 +0300
Make negative number their own token
The negation (-) operator will call Item->neg() one underlying numeric constants
and remove itself (like the NOT() function does today for other NOT functions.
This simplifies things
- -1 is not anymore an expression but a basic_const_item
- improves optimizer
- DEFAULT -1 doesn't need special handling anymore
- When we add DEFAULT expressions, -1 will be treated exactly like 1
- printing of items doesn't anymore put braces around all negative numbers
Other things fixed:
- Fixed that longlong converted to decimal's has a more appropriate size
- Fixed that "-0.0" read into a decimal is interpreted as 0.0
Decimals with float, double and decimal now works the following way:
- DECIMAL_NOT_SPECIFIED is used when declaring DECIMALS without a firm number
of decimals. It's only used in asserts and my_decimal_int_part.
- FLOATING_POINT_DECIMALS (31) is used to mark that a FLOAT or DOUBLE
was defined without decimals. This is regarded as a floating point value.
- Max decimals allowed for FLOAT and DOUBLE is FLOATING_POINT_DECIMALS-1
- Clients assumes that float and double with decimals >= NOT_FIXED_DEC are
floating point values (no decimals)
- In the .frm decimals=FLOATING_POINT_DECIMALS are used to define
floating point for float and double (31, like before)
To ensure compatibility with old clients we do:
- When storing float and double, we change NOT_FIXED_DEC to
FLOATING_POINT_DECIMALS.
- When creating fields from .frm we change for float and double
FLOATING_POINT_DEC to NOT_FIXED_DEC
- When sending definition for a float/decimal field without decimals
to the client as part of a result set we convert NOT_FIXED_DEC to
FLOATING_POINT_DECIMALS.
- variance() and std() has changed to limit the decimals to
FLOATING_POINT_DECIMALS -1 to not get the double converted floating point.
(This was to preserve compatiblity)
- FLOAT and DOUBLE still have 30 as max number of decimals.
Bugs fixed:
variance() printed more decimals than we support for double values.
New behaviour:
- Strings now have 38 decimals instead of 30 when converted to decimal
- CREATE ... SELECT with a decimal with > 30 decimals will create a column
with a smaller range than before as we are trying to preserve the number of
decimals.
Other changes
- We are now using the obsolete bit FIELDFLAG_LEFT_FULLSCREEN to specify
decimals > 31
- NOT_FIXED_DEC is now declared in one place
- For clients, NOT_FIXED_DEC is always 31 (to ensure compatibility).
On the server NOT_FIXED_DEC is DECIMAL_NOT_SPECIFIED (39)
- AUTO_SEC_PART_DIGITS is taken from DECIMAL_NOT_SPECIFIED
- DOUBLE conversion functions are now using DECIMAL_NOT_SPECIFIED instead of
NOT_FIXED_DEC
- Removed some QQ markers
- Removed some rows not compatible with valgrind 3.9.0
- Made mysql_install_db.sh more silent by default. --verbose now gives more information
- Added assert that auto-increment doesn't generate 0 (safety)
- Removed thd->set_time() in some places as it's set in init_for_queries()
- Fixed some --big tests in tokudb
- Fixed a bug in mysql_client_test.cc where sql_mode was not properly reset
- Removing the "diff_if_only_endspace_difference" argument from
MY_COLLATION_HANDLER::strnncollsp(), my_strnncollsp_simple(),
as well as in the function template MY_FUNCTION_NAME(strnncollsp)
in strcoll.ic
- Removing the "diff_if_only_space_different" from ha_compare_text(),
hp_rec_key_cmp().
- Adding a new function my_strnncollsp_padspace_bin() and reusing
it instead of duplicate code pieces in my_strnncollsp_8bit_bin(),
my_strnncollsp_latin1_de(), my_strnncollsp_tis620(),
my_strnncollsp_utf8_cs().
- Adding more tests for better coverage of the trailing space handling.
- Removing the unused definition of HA_END_SPACE_ARE_EQUAL
1. Fixing Field_time::get_equal_const_item() to pass TIME_FUZZY_DATES
and TIME_INVALID_DATES to get_time_with_conversion().
This is needed to make the recursively called Item::get_date() return
non-NULL values on garbage input. This makes Field_time::get_equal_const_item()
work consistently with how Item::val_time_packed() works.
2. Fixing Item::get_date() to return TIME'00:00:00' rather than
DATE'0000-00-00' on empty or garbage input when:
- TIME_FUZZY_DATES is enabled
- The caller requested a TIME value (by passing TIME_TIME_ONLY).
This is needed to avoid conversion of DATE'0000-00-00' to TIME
in get_time_with_conversion(), which would erroneously try to subtract
CURRENT_DATE from DATE'0000-00-00' and return TIME'-838:59:59' rather than
the desired zero value TIME'00:00:00'.
#1 and #2 fix these type of scripts to return one row with both
MyISAM and InnoDB, with and without an index on t1.b:
CREATE TABLE t1 (a ENUM('a'), b TIME, c INT, KEY(b));
INSERT INTO t1 VALUES ('','00:00:00',0);
SELECT * FROM t1 WHERE b='';
SELECT * FROM t1 WHERE a=b;
SELECT * FROM t1 IGNORE INDEX(b) WHERE b='';
SELECT * FROM t1 IGNORE INDEX(b) WHERE a=b;
Additionally, #1 and #2 fix the originally reported in MDEV-9604 crash
in Item::save_in_field(), because now execution goes through a different
path, so save_in_field() is called for a Item_time_literal instance
(which is non-NULL) rather than a Item_cache_str instance (which could
return NULL without setting null_value).
3. Fixing Field_temporal::get_equal_const_item_datetime() to enable
equal field propagation for DATETIME and TIMESTAMP in case of
comparison (e.g. when ANY_SUBST), for symmetry with
Field_newdate::get_equal_const_item(). This fixes a number of problems
with empty set returned on comparison to empty/garbage input.
Now all SELECT queries in this script return one row for MyISAM and InnoDB,
with and without an index on t1.b:
CREATE TABLE t1 (a ENUM('a'), b DATETIME, c INT, KEY(b));
INSERT INTO t1 VALUES ('','0000-00-00 00:00:00',0);
SELECT * FROM t1 WHERE b='';
SELECT * FROM t1 WHERE a=b;
SELECT * FROM t1 IGNORE INDEX(b) WHERE b='';
SELECT * FROM t1 IGNORE INDEX(b) WHERE a=b;
from Item_bool_func::get_mm_leaf() into Field_xxx::can_optimize_range().
This reduces the total amount of virtual calls. Also, it's a prerequisite
change for the pluggable data types.
