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Fix for BUG#11755168 '46895: test "outfile_loaddata" fails (reproducible)'.

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In sql_class.cc, 'row_count', of type 'ha_rows', was used as last argument for
ER_TRUNCATED_WRONG_VALUE_FOR_FIELD which is
"Incorrect %-.32s value: '%-.128s' for column '%.192s' at row %ld".
So 'ha_rows' was used as 'long'.
On SPARC32 Solaris builds, 'long' is 4 bytes and 'ha_rows' is 'longlong' i.e. 8 bytes.
So the printf-like code was reading only the first 4 bytes.
Because the CPU is big-endian, 1LL is 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x01
so the first four bytes yield 0. So the warning message had "row 0" instead of
"row 1" in test outfile_loaddata.test:
-Warning	1366	Incorrect string value: '\xE1\xE2\xF7' for column 'b' at row 1
+Warning	1366	Incorrect string value: '\xE1\xE2\xF7' for column 'b' at row 0

All error-messaging functions which internally invoke some printf-life function
are potential candidate for such mistakes.
One apparently easy way to catch such mistakes is to use
ATTRIBUTE_FORMAT (from my_attribute.h).
But this works only when call site has both:
a) the format as a string literal
b) the types of arguments.
So:
  func(ER(ER_BLAH), 10);
will silently not be checked, because ER(ER_BLAH) is not known at
compile time (it is known at run-time, and depends on the chosen
language).
And
  func("%s", a va_list argument);
has the same problem, as the *real* type of arguments is not
known at this site at compile time (it's known in some caller).
Moreover,
  func(ER(ER_BLAH));
though possibly correct (if ER(ER_BLAH) has no '%' markers), will not
compile (gcc says "error: format not a string literal and no format
arguments").

Consequences:
1) ATTRIBUTE_FORMAT is here added only to functions which in practice
take "string literal" formats: "my_error_reporter" and "print_admin_msg".
2) it cannot be added to the other functions: my_error(),
push_warning_printf(), Table_check_intact::report_error(),
general_log_print().

To do a one-time check of functions listed in (2), the following
"static code analysis" has been done:
1) replace
  my_error(ER_xxx, arguments for substitution in format)
with the equivalent
  my_printf_error(ER_xxx,ER(ER_xxx), arguments for substitution in
format),
so that we have ER(ER_xxx) and the arguments *in the same call site*
2) add ATTRIBUTE_FORMAT to push_warning_printf(),
Table_check_intact::report_error(), general_log_print()
3) replace ER(xxx) with the hard-coded English text found in
errmsg.txt (like: ER(ER_UNKNOWN_ERROR) is replaced with
"Unknown error"), so that a call site has the format as string literal
4) this way, ATTRIBUTE_FORMAT can effectively do its job
5) compile, fix errors detected by ATTRIBUTE_FORMAT
6) revert steps 1-2-3.
The present patch has no compiler error when submitted again to the
static code analysis above.
It cannot catch all problems though: see Field::set_warning(), in
which a call to push_warning_printf() has a variable error
(thus, not replacable by a string literal); I checked set_warning() calls
by hand though.

See also WL 5883 for one proposal to avoid such bugs from appearing
again in the future.

The issues fixed in the patch are:
a) mismatch in types (like 'int' passed to '%ld')
b) more arguments passed than specified in the format.
This patch resolves mismatches by changing the type/number of arguments,
not by changing error messages of sql/share/errmsg.txt. The latter would be wrong,
per the following old rule: errmsg.txt must be as stable as possible; no insertions
or deletions of messages, no changes of type or number of printf-like format specifiers,
are allowed, as long as the change impacts a message already released in a GA version.
If this rule is not followed:
- Connectors, which use error message numbers, will be confused (by insertions/deletions
of messages)
- using errmsg.sys of MySQL 5.1.n with mysqld of MySQL 5.1.(n+1)
could produce wrong messages or crash; such usage can easily happen if
installing 5.1.(n+1) while /etc/my.cnf still has --language=/path/to/5.1.n/xxx;
or if copying mysqld from 5.1.(n+1) into a 5.1.n installation.
When fixing b), I have verified that the superfluous arguments were not used in the format
in the first 5.1 GA (5.1.30 'bteam@astra04-20081114162938-z8mctjp6st27uobm').
Had they been used, then passing them today, even if the message doesn't use them
anymore, would have been necessary, as explained above.
This commit is contained in:
Guilhem Bichot
2011-05-16 22:04:01 +02:00
parent 4731736320
commit 25221cccd2
28 changed files with 133 additions and 137 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
sql/sql_parse.cc
View File

@ -1,4 +1,4 @@
/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@ -11,7 +11,7 @@
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#define MYSQL_LEX 1
#include "mysql_priv.h"
@ -3981,8 +3981,7 @@ end_with_restore_list:
hostname_requires_resolving(user->host.str))
push_warning_printf(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
ER_WARN_HOSTNAME_WONT_WORK,
ER(ER_WARN_HOSTNAME_WONT_WORK),
user->host.str);
ER(ER_WARN_HOSTNAME_WONT_WORK));
// Are we trying to change a password of another user
DBUG_ASSERT(user->host.str != 0);
if (strcmp(thd->security_ctx->user, user->user.str) ||
@ -5889,7 +5888,7 @@ mysql_new_select(LEX *lex, bool move_down)
lex->nest_level++;
if (lex->nest_level > (int) MAX_SELECT_NESTING)
{
my_error(ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT,MYF(0),MAX_SELECT_NESTING);
my_error(ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT, MYF(0));
DBUG_RETURN(1);
}
select_lex->nest_level= lex->nest_level;
@ -6936,7 +6935,7 @@ bool reload_acl_and_cache(THD *thd, ulong options, TABLE_LIST *tables,
When an error is returned, my_message may have not been called and
the client will hang waiting for a response.
*/
my_error(ER_UNKNOWN_ERROR, MYF(0), "FLUSH PRIVILEGES failed");
my_error(ER_UNKNOWN_ERROR, MYF(0));
}
}