perl debugger not working in taint mode

[p5pRT]

Migrated from rt.perl.org#76872 (status was 'resolved')

Searchable as RT76872$

[p5pRT]

From swamy.sangamesh@gmail.com

I tried to send report using perlbug tool, but looks like report has not
been sent, hence sending it directly.

Getting Insecure dependency error when used perl debugger with taint mode
/usr/bin/perl -wT . This issue seems to be common in all the platforms as i
tested it in aix and linux. it appears in latest perl also, in perl-5.12.1
and 5.10.0, 5.10.1.
not facing any issue in perl-5.8.8.

Here is the error message​:

$ perl -dT Mytest.pm

Loading DB routines from perl5db.pl version 1.3
Editor support available.

Enter h or `h h' for help, or `man perldebug' for more help.

Insecure dependency in eval while running with -T switch at
/usr/lib/perl5/5.10.0/i386-linux-thread-multi/File/Glob.pm line 92.
Compilation failed in require at Mytest.pm line 34.
at Mytest.pm line 34
  Mytest​::BEGIN() called at
/usr/lib/perl5/5.10.0/i386-linux-thread-multi/File/Glob.pm line 34
  eval {...} called at
/usr/lib/perl5/5.10.0/i386-linux-thread-multi/File/Glob.pm line 34
BEGIN failed--compilation aborted at Mytest.pm line 34.
at Mytest.pm line 34
Debugged program terminated. Use q to quit or R to restart,
  use o inhibit_exit to avoid stopping after program termination,
  h q, h R or h o to get additional info.
  DB<1>

And content of Mytest.pm and Mytest.xs look like

$ cat Mytest.pm
#!/usr/bin/perl -wT
package Mytest;
use XSLoader ();

BEGIN {
  XSLoader​::load('Mytest');
}
BEGIN {
  XSLoader​::load('Mytest');
  my $var = defined($0)? UNDEFINE : 1;
}

sub func_test {
  glob("check");
  return 1;
}

1;

$ cat Mytest.xs
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include "ppport.h"
#define UNDEFINE 0

MODULE = Mytest PACKAGE = Mytest

IV
UNDEFINE()
  ALIAS​:
  UNDEFINE = 0
  CODE​:
  switch(ix) {
  case 0​: RETVAL = UNDEFINE; break;
  }
  OUTPUT​:
  RETVAL

This issue happens when used taint mode in debugger, if we invoke debugger
without taint mode then debugger works fine.
Looks like some drastic changes happened in perl-5.10.0

--
Thanks & Regards,
Sangamesh

[p5pRT]

From @ksangeek

I am also facing the same issue .. Can someone please give an idea on
what may be going wrong.

Thanks & Regards,
Sangeeth K

[p5pRT]

From [Unknown Contact. See original ticket]

I am also facing the same issue .. Can someone please give an idea on
what may be going wrong.

Thanks & Regards,
Sangeeth K

[p5pRT]

swamy.sangamesh@gmail.com - Status changed from 'new' to 'open'

[p5pRT]

From swamy.sangamesh@gmail.com

Please can someone take look at this issue.

Looks like this is happening if we have two BEGIN blocks and glob() is
called. No issue is seen if we have only one BEGIN block.

[p5pRT]

From @iabyn

On Sat, Jul 31, 2010 at 05​:56​:17AM -0700, sangamesh M wrote​:

Getting Insecure dependency error when used perl debugger with taint mode
/usr/bin/perl -wT . This issue seems to be common in all the platforms as i
tested it in aix and linux. it appears in latest perl also, in perl-5.12.1
and 5.10.0, 5.10.1.
not facing any issue in perl-5.8.8.

This is now fixed in bleadperl with the commit below​:

commit 07004eb
Author​: David Mitchell <davem@​iabyn.com>
AuthorDate​: Wed Aug 25 12​:15​:41 2010 +0100
Commit​: David Mitchell <davem@​iabyn.com>
CommitDate​: Wed Aug 25 12​:15​:41 2010 +0100

  don't taint $DB​::sub
 
  [perl #76872] showed a case where code like the following, run under -d,
  would cause $DB​::sub to get set​:
 
  $tainted_expression && func()
 
  The tainted expression sets PL_tainted, so calling func() under -d, which
  sets $DB​::sub, causes it to get tainted.
 
  Consequently any further sub calls would set PL_tainted while getting the
  old value of $DB​::sub (and cause the new value to be tainted too), and if
  the sub was XS, then its code would be executed with PL_tainted set.
  It isn't an issue with perl subs as the first nextstate op resets
  PL_tainted.

M MANIFEST
M lib/perl5db.t
A lib/perl5db/t/taint
M util.c

--
The optimist believes that he lives in the best of all possible worlds.
As does the pessimist.

[p5pRT]

@iabyn - Status changed from 'open' to 'resolved'