it was race condition prone. instead use either a pair of my_delete()
calls with already resolved paths, or a safe high-level function
my_handler_delete_with_symlink(), like MyISAM and Aria already do.
TOCTOU bug. The path is checked to be valid, symlinks are resolved.
Then the resolved path is opened. Between the check and the open,
there's a window when one can replace some path component with a
symlink, bypassing validity checks.
Fix: after we resolved all symlinks in the path, don't allow open()
to resolve symlinks, there should be none.
Compared to the old MyISAM/Aria code:
* fastpath. Opening of not-symlinked files is just one open(),
no fn_format() and lstat() anymore.
* opening of symlinked tables doesn't do fn_format() and lstat() either.
it also doesn't to realpath() (which was lstat-ing every path
component), instead if opens every path component with O_PATH.
* share->data_file_name stores realpath(path) not readlink(path). So,
SHOW CREATE TABLE needs to do lstat/readlink() now (see ::info()),
and certain error messages (cannot open file "XXX") show the real
file path with all symlinks resolved.
my_thread_global_init() + my_thrad_global_end() repeatadily.
This caused THR_KEY_mysys to be allocated multiple times.
Deletion of THR_KEY_mysys was originally in my_thread_global_end() but was
moved to my_end() as DBUG uses THR_KEY_mysys and DBUG is released after
my_thread_global_end() is called.
Releasing DBUG before my_thread_global_end() and move THR_KEY_mysys back
into my_thread_global_end() could be a solution, but as safe_mutex and other
things called by my_thread_global_end is using DBUG it may not be completely
safe.
To solve this, I used the simple solution to add a marker that THR_KEY_mysys
is created and not re-create it in my_thread_global_init if it already
exists.
- Atomic writes are enabled by default
- Automatically detect if device supports atomic write and use it if
atomic writes are enabled
- Remove ATOMIC WRITE options from CREATE TABLE
- Atomic write is a device option, not a table options as the table may
crash if the media changes
- Add support for SHANNON SSD cards
MariaDB Server is unnecessarily evaluating the arguments of
DBUG_PRINT() macros when the label is not defined.
The macro DBUG_LOG() for C++ operator<< output which was added for
InnoDB diagnostics in MySQL 5.7 is missing from MariaDB. Unlike the
MySQL 5.7 implementation, MariaDB will avoid allocating and
initializing the output string when the label is not defined.
Introduce DBUG_OUT("crypt") and DBUG_OUT("checksum") for some InnoDB
diagnostics, replacing some use of ib::info().
check_contains() fixed. When an item of an array is a complex
structure, it can be half-read after the end of the recursive
check_contains() call. So we just manually get to it's ending.
* don't issue an error for ER_KEY_BASED_ON_GENERATED_VIRTUAL_COLUMN
* support keyread on vcols
* callback into the server to compute vcol values from mi_check/mi_repair
* DMLs just work. Automatically.
- Used same fix as for MyISAM: High level collation byte stored in unused
bit_end position.
- Moved language from header to base_info
- Removed unused bit_end part in HA_KEY_SEG
Partially backporting MDEV-9874 from 10.2 to 10.0
READ_INFO::read_field() raised the ER_INVALID_CHARACTER_STRING error
when reading an escape character followed by a multi-byte character.
Raising wellformedness errors in READ_INFO::read_field() was wrong,
because the main goal of READ_INFO::read_field() is to *unescape* the
data which was presumably escaped using mysql_real_escape_string(),
using the same character set with the one specified in
"LOAD DATA INFILE ... CHARACTER SET ..." (or assumed by default).
During LOAD DATA, multi-byte characters are not always scanned as a single
entity! In case of escaped data, parts of a multi-byte character can be
scanned on different loop iterations. So the old code erroneously tested
welformedness in the middle of a multi-byte character.
Moreover, the data after unescaping can go into a BLOB field, not a text field.
Wellformedness tests are meaningless in this case.
Ater this patch, wellformedness is only checked later, during
Field::store(str,length,cs) time. The loop that scans bytes only
makes sure to revert the changes made by mysql_real_escape_string().
Note, in some cases users can supply data which did not really go through
mysql_real_escape_string() and was escaped by some other means,
or was not escaped at all. The file reported in this MDEV contains
the string "\ä", which is an example of such improperly escaped data, as
- either there should be two backslashes: "\\ä"
- or there should be no backslashes at all: "ä"
mysql_real_escape_string() could not generate "\ä".
capabilities(in upper 32bits) were sent as 0 on 32bit Windows. They were
reset because CLIENT_SSL, CLIENT_COMPRESS and CLIENT_SSL_VERIFY_SERVER_CERT were defined as UL
Plus MARIADB_CLIENT_STMT_BULK_OPERATIONS was defined as 1UL << 34, and that is undefined operation.
ANALYSIS:
=========
'CREATE TABLE' query with a large value for 'CONNECTION'
string reports an incorrect error.
The length of connection string is stored in .frm in two
bytes (max value= 65535). When the string length exceeds
the max value, the length is truncated to fit the two
bytes limit. Further processing leads to reading only a
part of the string as the length stored is incorrect. The
remaining part of the string is treated as engine type and
hence results in an error.
FIX:
====
We are now restricting the connection string length to 1024.
An appropriate error is reported if the length crosses this
limit.
NOTE:
=====
The 'PASSWORD' table option is documented as unused and
processed within a dead code. Hence it will not cause
similar issue with large strings.
Clean-up nolock.h: it doesn't serve any purpose anymore. Appropriate code moved
to x86-gcc.h and my_atomic.h.
If gcc sync bultins were detected, we want to make use of them independently of
__GNUC__ definition. E.g. XLC simulates those, but doesn't define __GNUC__.
HS/Spider: According to AIX manual alloca() returns char*, which cannot be
casted to any type with static_cast. Use explicit cast instead.
MDL: Removed namemangling pragma, which didn't let MariaDB build with XLC.
WSREP: _int64 seem to be conflicting name with XLC, replaced with _integer64.
CONNECT: RTLD_NOLOAD is GNU extention. Removed rather meaningless check if
library is loaded. Multiple dlopen()'s of the same library are permitted,
and it never gets closed anyway. Except for error, which was a bug: it may
close library, which can still be referenced by other subsystems.
InnoDB: __ppc_get_timebase() is GNU extention. Only use it when __GLIBC__ is
defined.
Based on contribution by flynn1973.
The crash is caused by macro uint3korr() accessing memory (1 byte) past
the end of allocated page. The macro is written such it reads 4 bytes
instead of 3 and discards the value of the last byte.
However, it is not always guaranteed that all uint3korr accesses will be
valid (i.e that the caller allocates an extra byte after the value).
In particular, the tree in Item_func_group_concat does not account for
any extra bytes that it would need for comparison of keys in some cases
(Field_newdate::cmp, Field_medium::cmp)
The fix change uint3korr so it does not access extra bytes.
