Description: Sometimes when killing the mysql command line client with
KILL -2(SIGINT), mysql client core dumps as a result of a double free or
corruption.
Analysis: When we run the mysql client in command line mode it will goes
to mysql_end() and frees many data structures. At the same time (i.e
after some data structures are freed), if we give "KILL -2" signal then
the signal will be handled with function handle_kill_signal() and as
part of it will again calls mysql_end() and goes with free() to the
already freed data structure for batch_readline_end() function, which
causes core dump.
Fix: Ignoring SIGQUIT and SIGINT signals when cleanup process starts.
This will help in resolving the double free issues, which occurs
in case the signal handler function is started in between of the
clean up function.
For 5.6 we need to ignore SIGHUP also.
Problem: While printing the Server version, mysql client
doesn't check for the buffer overflow in a
String variable.
Solution: Used a different print function which checks the
allocated length before writing into the string.
INTERACTIVE MODE
In interactive mode, libedit/readline allocates memory
for every new line entered & later the allocated memory
never gets freed.
Fixed by freeing the allocated memory blocks appropriately.
IN A SQL STATEMENT
While processing each lines entered at the prompt,
mysql client appends a '\n' to all the lines except
for delimiter commands. However the same logic must
not apply if 'delimiter' is part of a string or a
comment, for which a '\n' should be added.
Fixed by adding appropriate checks.
Added a test case.
WHEN DBNAME CONTAINS MULTIPLE QUOTES
MySQL client's USE command might fail if the
database name contains multiple quotes (backticks).
The reason behind the failure being the method
that client uses to remove/escape the quotes
while parsing the USE command's option (dbname),
where the option parsing might terminate if a
matching quote is found.
Also, C-APIs like mysql_select_db() expect a
normalized dbname. Now, in certain cases, client
might fail to normalize dbname similar to that of
server and hence mysql_select_db() would fail.
Fixed by getting the normalized dbname (indirectly)
from the server by directly sending the "USE dbanme"
as query to the server followed by a "SELECT DATABASE()".
The above steps are only performed if number of quotes
in the dbname is greater than 2. Once the normalized
dbname is received, the original db is restored.
SHOW 2012 INSTEAD OF 2011
* Added a new macro to hold the current year :
COPYRIGHT_NOTICE_CURRENT_YEAR
* Modified ORACLE_WELCOME_COPYRIGHT_NOTICE macro
to take the initial year as parameter and pick
current year from the above mentioned macro.
Problem description:
Giving "help 'contents'" in the mysql client as a first statement
gives error
Analysis:
In com_server_help() function the "server_cmd" variable was
initialised with buffer->ptr(). And the "server_cmd" variable is not
updated since we are passing "'contents'"(with single quote) so the
buffer->ptr() consists of the previous buffer values and it was sent
to the mysql_real_query() hence we are getting error.
Fix:
We are not initialising the "server_cmd" variable and we are updating
the variable with "server_cmd= cmd_buf" in any of the case i.e with
single quote or without single quote for the contents.
As part of error message improvement, added new error message in case
of "help 'contents'".
1. Clear text password client plugin disabled by default.
2. Added an environment variable LIBMYSQL_ENABLE_CLEARTEXT_PLUGIN, that
when set to something starting with '1', 'Y' or 'y' will enable the clear
text
plugin for all connections.
3. Added a new mysql_options() option : MYSQL_ENABLE_CLEARTEXT_PLUGIN
that takes an my_bool argument. When the value of the argument is non-zero
the clear text plugin is enabled for this connection only.
4. Added an enable-cleartext-plugin config file option that takes a numeric
argument. If the numeric value of the numeric argument is non-zero the
clear
text plugin is enabled for the connection
5. Added a boolean command line option "--enable_cleartext_plugin" to
mysql, mysqlslap and mysqladmin. When specified it will call mysql_options
with the effect of #3
6. Added a new CLEARTEXT option to the connect command in mysqltest.
When specified it will enable the cleartext plugin for usage.
7. Added test cases and updated existing ones that need the clear text
plugin.
SYSTEM VARIABLE NAME SQL_MAX_JOIN_SI
BACKGROUND:
ER_TOO_BIG_SELECT refers to SQL_MAX_JOIN_SIZE, which is the
old name for MAX_JOIN_SIZE.
FIX:
Support for old name SQL_MAX_JOIN_SIZE is removed in MySQL 5.6
and is renamed as MAX_JOIN_SIZE.So the errmsg.txt
and mysql.cc files have been updated and the corresponding result
files have also been updated.
TOOLS
Backport a fix for Bug 57094 from 5.5.
The following revision was backported:
# revision-id: alexander.nozdrin@oracle.com-20101006150613-ls60rb2tq5dpyb5c
# parent: bar@mysql.com-20101006121559-am1e05ykeicwnx48
# committer: Alexander Nozdrin <alexander.nozdrin@oracle.com>
# branch nick: mysql-5.5-bugteam-bug57094
# timestamp: Wed 2010-10-06 19:06:13 +0400
# message:
# Fix for Bug 57094 (Copyright notice incorrect?).
#
# The fix is to:
# - introduce ORACLE_WELCOME_COPYRIGHT_NOTICE define to have a single place
# to specify copyright notice;
# - replace custom copyright notices with ORACLE_WELCOME_COPYRIGHT_NOTICE
# in programs.
batch_readline_init() was modified - return an error
if the input source is a directory or a block device.
This follow-up is necessary because on some platforms,
such as Solaris, call to read() from directory may be
successful.
if the standard input is a directory.
The problem is that mysql monitor try to read from stdin without
checking input source type.
The solution is to stop reading data from standard input if a call
to read(2) failed.
A new test case was added into mysql.test.
After dropping and recreating the database specified along with --one-database
option at command line, mysql client keeps filtering the statements even after
the execution of a 'USE' command on the same database.
--one-database option enables the filtering of statements when the current
database is not the one specified at the command line. However, when the same
database is dropped and recreated the variable (current_db) that holds the
inital database name gets altered. This bug exploits the fact that current_db
initially gets set to null value (0) when a 'use db_name' follows the recreation
of same database db_name (speficied at the command line) and hence skip_updates
gets set to 1, which inturn triggers the further filtering of statements.
Fixed by making get_current_db() a no-op function when one_database is set,
and hence, under that condition current_db will not get altered.
Note, however the value of current_db can change when we execute 'connect'
command with a differnet database to reconnect to the server, in which case,
the behavior of --one-database will be formulated using this new database.
The fix is to:
- introduce ORACLE_WELCOME_COPYRIGHT_NOTICE define to have a single place
to specify copyright notice;
- replace custom copyright notices with ORACLE_WELCOME_COPYRIGHT_NOTICE
in programs.
#ifdef THREAD removed from mysql.cc.
No reason was found for this limitation to persist.
per-file comments:
client/mysql.cc
Bug#54466 client 5.5 built from source lacks "pager" support
now we have USE_POPEN always if not __WIN__
mysql-test/r/mysql.result
Bug#54466 client 5.5 built from source lacks "pager" support
result updated.
mysql-test/t/mysql.test
Bug#54466 client 5.5 built from source lacks "pager" support
test case added.
Fix warnings flagged by the new warning option -Wunused-but-set-variable
that was added to GCC 4.6 and that is enabled by -Wunused and -Wall. The
option causes a warning whenever a local variable is assigned to but is
later unused. It also warns about meaningless pointer dereferences.
Essentially, the problem is that safemalloc is excruciatingly
slow as it checks all allocated blocks for overrun at each
memory management primitive, yielding a almost exponential
slowdown for the memory management functions (malloc, realloc,
free). The overrun check basically consists of verifying some
bytes of a block for certain magic keys, which catches some
simple forms of overrun. Another minor problem is violation
of aliasing rules and that its own internal list of blocks
is prone to corruption.
Another issue with safemalloc is rather the maintenance cost
as the tool has a significant impact on the server code.
Given the magnitude of memory debuggers available nowadays,
especially those that are provided with the platform malloc
implementation, maintenance of a in-house and largely obsolete
memory debugger becomes a burden that is not worth the effort
due to its slowness and lack of support for detecting more
common forms of heap corruption.
Since there are third-party tools that can provide the same
functionality at a lower or comparable performance cost, the
solution is to simply remove safemalloc. Third-party tools
can provide the same functionality at a lower or comparable
performance cost.
The removal of safemalloc also allows a simplification of the
malloc wrappers, removing quite a bit of kludge: redefinition
of my_malloc, my_free and the removal of the unused second
argument of my_free. Since free() always check whether the
supplied pointer is null, redudant checks are also removed.
Also, this patch adds unit testing for my_malloc and moves
my_realloc implementation into the same file as the other
memory allocation primitives.
Apart strict-aliasing warnings, fix the remaining warnings
generated by GCC 4.4.4 -Wall and -Wextra flags.
One major source of warnings was the in-house function my_bcmp
which (unconventionally) took pointers to unsigned characters
as the byte sequences to be compared. Since my_bcmp and bcmp
are deprecated functions whose only difference with memcmp is
the return value, every use of the function is replaced with
memcmp as the special return value wasn't actually being used
by any caller.
There were also various other warnings, mostly due to type
mismatches, missing return values, missing prototypes, dead
code (unreachable) and ignored return values.
strict aliasing violations.
Essentially, the problem is that large parts of the server were
developed in simpler times (last decades, pre C99 standard) when
strict aliasing and compilers supporting such optimizations were
rare to non-existent. Thus, when compiling the server with a modern
compiler that uses strict aliasing rules to perform optimizations,
there are several places in the code that might trigger undefined
behavior.
As evinced by some recent bugs, GCC does a somewhat good of job
misoptimizing such code, but on the other hand also gives warnings
about suspicious code. One problem is that the warnings aren't
always accurate, yet we can't afford to just shut them off as we
might miss real cases. False-positive cases are aggravated mostly
by casts that are likely to trigger undefined behavior.
The solution is to start a cleanup process focused on fixing and
reducing the amount of strict-aliasing related warnings produced
by GCC and others compilers. A good deal of noise reduction can
be achieved by just removing useless casts that are product of
historical cruft and are likely to trigger undefined behavior if
dereferenced.
Fix various mismatches between function's language linkage. Any
particular function that is declared in C++ but should be callable
from C must have C linkage. Note that function types with different
linkages are also distinct. Thus, if a function type is declared in
C code, it will have C linkage (same if declared in a extern "C"
block).
ChangeSet@1.2703, 2007-12-07 09:35:28-05:00, cmiller@zippy.cornsilk.net +40 -0
Bug#13174: SHA2 function
Patch contributed from Bill Karwin, paper unnumbered CLA in Seattle
Implement SHA2 functions.
Chad added code to make it work with YaSSL. Also, he removed the
(probable) bug of embedded server never using SSL-dependent
functions. (libmysqld/Makefile.am didn't read ANY autoconf defs.)
Function specification:
SHA2( string cleartext, integer hash_length )
-> string hash, or NULL
where hash_length is one of 224, 256, 384, or 512. If either is
NULL or a length is unsupported, then the result is NULL. The
resulting string is always the length of the hash_length parameter
or is NULL.
Include the canonical hash examples from the NIST in the test
results.
---
Polish and address concerns of reviewers.
Conflicts:
Text conflict in client/mysqlbinlog.cc
Text conflict in mysql-test/Makefile.am
Text conflict in mysql-test/collections/default.daily
Text conflict in mysql-test/r/mysqlbinlog_row_innodb.result
Text conflict in mysql-test/suite/rpl/r/rpl_typeconv_innodb.result
Text conflict in mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test
Text conflict in mysql-test/suite/rpl/t/rpl_row_create_table.test
Text conflict in mysql-test/suite/rpl/t/rpl_slave_skip.test
Text conflict in mysql-test/suite/rpl/t/rpl_typeconv_innodb.test
Text conflict in mysys/charset.c
Text conflict in sql/field.cc
Text conflict in sql/field.h
Text conflict in sql/item.h
Text conflict in sql/item_func.cc
Text conflict in sql/log.cc
Text conflict in sql/log_event.cc
Text conflict in sql/log_event_old.cc
Text conflict in sql/mysqld.cc
Text conflict in sql/rpl_utility.cc
Text conflict in sql/rpl_utility.h
Text conflict in sql/set_var.cc
Text conflict in sql/share/Makefile.am
Text conflict in sql/sql_delete.cc
Text conflict in sql/sql_plugin.cc
Text conflict in sql/sql_select.cc
Text conflict in sql/sql_table.cc
Text conflict in storage/example/ha_example.h
Text conflict in storage/federated/ha_federated.cc
Text conflict in storage/myisammrg/ha_myisammrg.cc
Text conflict in storage/myisammrg/myrg_open.c
Conflicts:
Text conflict in client/mysqlbinlog.cc
Text conflict in mysql-test/r/explain.result
Text conflict in mysql-test/r/subselect.result
Text conflict in mysql-test/r/subselect3.result
Text conflict in mysql-test/r/type_datetime.result
Text conflict in sql/share/Makefile.am
