MySQL Bugs: #20559: Program crashes when using server-side prepare

Bug #20559	Program crashes when using server-side prepare
Submitted:	20 Jun 2006 9:03	Modified:	3 Jan 2007 0:11
Reporter:	Steve Hay	Email Updates:
Status:	Closed	Impact on me:	None
Category:	Connectors: DBD::mysql ( Perl )	Severity:	S2 (Serious)
Version:	3.0006_1	OS:	Windows (Windows XP)
Assigned to:	Bugs System	CPU Architecture:	Any

Description:
I've found another problem with the new server side prepare statements in 3.0006_1.

The program below crashes here:

mysql_st_prepare(sv * 0x0195b0a8, imp_sth_st * 0x0183b008, char * 0x01839470, sv * 0x0000002a) line 2311 + 21 bytes
XS_DBD__mysql__st__prepare(cv * 0x0195850c) line 427 + 42 bytes
[...]

If I delete the " FOR UPDATE" from the SELECT statement then it outputs these errors instead:

FREE ERROR BIND!FREE ERROR FBIND!

If I turn off server side prepare then it works fine, with or without the " FOR UPDATE" clause.

How to repeat:
dbi.pl
------
use strict;
use warnings;
use DBI qw(:sql_types);
my $tmp_dbh = DBI->connect(
  'dbi:mysql:database=mysql', 'root', undef,
  { AutoCommit => 1, PrintError => 0, RaiseError => 1 }
);
$tmp_dbh->do('CREATE DATABASE IF NOT EXISTS test');
$tmp_dbh->disconnect();
my $dsn = 'dbi:mysql:database=test;mysql_server_prepare=1';    # Crashes
#my $dsn = 'dbi:mysql:database=test;mysql_emulated_prepare=1'; # OK
my $dbh = DBI->connect(
  $dsn, 'root', undef,
  { AutoCommit => 1, PrintError => 0, RaiseError => 1 }
);
$dbh->do('DROP TABLE IF EXISTS foo');
$dbh->do(qq{CREATE TABLE foo (
  id  INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
  num INT
) ENGINE=InnoDB});
$dbh->trace(3, 'dbitrace.txt');
my $sql = 'SELECT num FROM foo WHERE id = ? FOR UPDATE';
my $sth = $dbh->prepare($sql);
$sth->bind_param(1, 1);
$sth->execute();
my $rows = $sth->fetchall_arrayref({});
$sth->finish();
$dbh->disconnect();

Suggested fix:
Wish I had one!

Thank you for the bug report. I installed DBD according the below
instructions (2 weeks ago):

ActivePerl offers a PPM archive of DBD::mysql. All you need to do is typing

  ppm
  install DBI
  install DBD-mysql

and testing against a 5.0 server I was unable to repeat your test case.

Which server version are you using?

I'm running 4.1.14.

What version of DBD-mysql are you running, though?  I'm not familiar with the PPM installation process that you've used, but it might only install the latest *stable* version (3.0006), whereas my bug report is specifically related to the *development* version (3.0006_1) because only that contains the server-side prepare support.

You can determine the version in use by running:
perl -MDBD::mysql -e "print $DBD::mysql::VERSION"

Yes it is a different version. How you installed the version:
3.0006_1?

Thanks in advance.

Well, I'm sure Patrick knows how I installed it, but for your information:

I downloaded DBD-mysql-3.0006_1 from http://search.cpan.org/dist/DBD-mysql/, extracted the archive, and then ran the usual sequence of commands for building a perl module, namely:

perl Makefile.PL
nmake
nmake test
nmake install

Steve,

I have tested this with the latest 3.0007/7_1 on UNIX, and I think it is fixed. I do not have a windows set up yet (will later this week, next week). Could you please see if the latest DBD::mysql fixes this?

Thanks!

Patrick,

I just tried this again on Windows XP (VC++ 6.0) using 3.0007_1 and the program still crashes, I'm afraid.

I'm running perl 5.8.8 and mysql 4.1.14.

Hi Patrick,

I've just tried this again with 3.0008_1 and it is now a little better, although still not fixed.

The program no longer crashes, but still outputs:

FREE ERROR BIND!FREE ERROR  FBIND!

when run with server-side prepare switched on.  (When it is switched off these errors do not appear.)

I also find that the "stable" version, 3.0008, behaves in the same way.

Steve

Steve,

This is still on win xp?

Thanks!

Patrick

Yes, still XP SP2, all built using VC++ 6.0.

Steve

There is similar bug #23467

I just want to report that I am having the same problem:

FREE ERROR BIND!FREE ERROR  FBIND!FREE ERROR BIND!FREE ERROR  FBIND!

I am using DBD::mysql 3.0008, DBI 1.53, perl 5.8.8 and mysql 5.0.24-standard

Regards,

Gustavo Delfino

perl -V
Summary of my perl5 (revision 5 version 8 subversion 8) configuration:
  Platform:
    osname=linux, osvers=2.6.9-42.0.3.elsmp, archname=i686-linux
    uname='linux **removed** 2.6.9-42.0.3.elsmp #1 smp fri oct 6 06:21:39 cdt 2006 i686 i686 i386 gnulinux '
    config_args='-de'
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=undef use5005threads=undef useithreads=undef usemultiplicity=undef
    useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
    use64bitint=undef use64bitall=undef uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-fno-strict-aliasing -pipe -Wdeclaration-after-statement -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/gdbm',
    optimize='-O2',
    cppflags='-fno-strict-aliasing -pipe -Wdeclaration-after-statement -I/usr/local/include -I/usr/include/gdbm'
    ccversion='', gccversion='3.4.6 20060404 (Red Hat 3.4.6-3)', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
    alignbytes=4, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib
    libs=-lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lc
    perllibs=-lnsl -ldl -lm -lcrypt -lutil -lc
    libc=/lib/libc-2.3.4.so, so=so, useshrplib=false, libperl=libperl.a
    gnulibc_version='2.3.4'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fpic', lddlflags='-shared -L/usr/local/lib'

Characteristics of this binary (from libperl): 
  Compile-time options: PERL_MALLOC_WRAP USE_LARGE_FILES USE_PERLIO
  Built under linux
  Compiled at Nov  5 2006 16:43:26
  @INC:
    /usr/local/lib/perl5/5.8.8/i686-linux
    /usr/local/lib/perl5/5.8.8
    /usr/local/lib/perl5/site_perl/5.8.8/i686-linux
    /usr/local/lib/perl5/site_perl/5.8.8
    /usr/local/lib/perl5/site_perl
    .

I had the same problem with dev-perl/DBD-mysql 3.0002_p4
After upgrade to 3.0008 version problem dissapeared.

In reply to Sergey Perminov's comment: upgrading to 3.0008 is bound to "fix" the problem, because as stated in my original report, the problem only occurs when using the new server-side prepare feature, which is only in the development versions, e.g. 3.0008_1. The stable versions (e.g. 3.0008) only have the old emulated prepare feature which didn't have the bug to start with.

I still experience the FREE ERROR [F]BIND warnings, albeit without a crash anymore, when using 3.0008_1.

The "FREE BIND" (and similar) error messages will no longer show up in the DBD::mysql development tree, because the duplicate freeing of bind data has been fixed. This will be included in the next release (probably 4.001).

Thanks for the bug report.

Actually, this should be fixed in the current 4.00 version. Ranger fixed the problem with the fbind structure, and I had fixed the crash (which I found when using DBD::mysql with mod_perl) in 3.0008, and removed the 'FREE BIND' error messages which still were occurring even when there was no problem.

I have the same problem getting a lot of "FREE ERROR BIND!FREE ERROR FBIND!" with the DBD-mysql-driver using the version 4.00.1 on gentoo-linux. (I use the MySQL-backend for the bayes-spam-filter in SpamAssassin)