no re 'taint' -- does not work

[p5pRT]

Migrated from rt.perl.org#1824 (status was 'resolved')

Searchable as RT1824$

[p5pRT]

From @muir

---------------- cut here -----------------------
#!/bin/sh
exec env PT=zz/yy perl -Tx $0
#!/usr/local/bin/perl -T

no re 'taint';
my $pcold = "/yy";
my $tainted;
if ($ENV{'PT'} =~ m,^(.*)\Q$pcold\E$,) {
  $tainted = "$1/pp";
}

print (STDERR is_tainted($tainted) ? "TAINTED\n" : "NOT TAINTED\n");

sub is_tainted
{
  return ! eval {
  join('',@​_), kill 0;
  1;
  };
}
---------------- cut here -----------------------

The above prints "TAINTED" on 5.005_02 and 5.005_03.

It shouldn't.

Interestingly enough, substituting "/yy" for "\Q$pcold\E" fixes
the problem. Why?

Thanks,
-Dave

Perl Info

Site configuration information for perl 5.00502:

Configured by markm at $Date: 1999/01/17 09:53:34 $.

Summary of my perl5 (5.0 patchlevel 5 subversion 2) configuration:
  Platform:
    osname=freebsd, osvers=3.0-current, archname=i386-freebsd
    uname='freebsd 3.0-current #0: '
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=undef useperlio=undef d_sfio=undef
  Compiler:
    cc='cc', optimize='undef', gccversion=2.7.2.1
    cppflags=''
    ccflags =''
    stdchar='char', d_stdstdio=undef, usevfork=true
    intsize=4, longsize=4, ptrsize=4, doublesize=8
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
    alignbytes=4, usemymalloc=n, prototype=define
  Linker and Libraries:
    ld='ld', ldflags ='-Wl,-E '
    libpth=/usr/lib
    libs=-lm -lc -lcrypt
    libc=undef, so=so, useshrplib=true, libperl=libperl.so.3
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' '
    cccdlflags='-DPIC -fpic', lddlflags='-shared '

Locally applied patches:
    


@INC for perl 5.00502:
    /usr/libdata/perl/5.00502/mach
    /usr/libdata/perl/5.00502
    /usr/local/lib/perl5/site_perl/5.005/i386-freebsd
    /usr/local/lib/perl5/site_perl/5.005
    .


Environment for perl 5.00502:
    HOME=/home/muir
    LANG (unset)
    LD_LIBRARY_PATH=.:/usr/lib:/usr/local/lib
    LOGDIR (unset)
    PATH=.:/home/muir/bin/idiom:/home/muir/bin:/home/muir/bin/share:/bin:/usr/bin:/sbin:/usr/sbin:/usr/local/shbin:/usr/local/sbin:/usr/local/bin:/usr/local/ptybin:/usr/X11R6/bin:/usr/bin/X11:/usr/local/tex/bin:/usr/ucb:/usr/bin:/bin:/etc:/usr/etc:/usr/games:/lib:/usr/lib:/usr/local/java/bin:/usr/lib/uucp:/usr/openwin/bin:/usr/openwin/bin/xview:/usr/openwin/demo:/usr/adm:/home/muir/tmp
    PERL_BADLANG (unset)
    SHELL=/bin/tcsh

[p5pRT]

From [Unknown Contact. See original ticket]

This appears to still be true in bleadperl.

#!/bin/sh
exec env PT=zz/yy perl -Tx $0
#!/usr/local/bin/perl -T

no re 'taint';
my $pcold = "/yy";
my $tainted;
if ($ENV{'PT'} =~ m,^(.*)\Q$pcold\E$,) {
  $tainted = "$1/pp";
}

print (STDERR is_tainted($tainted) ? "TAINTED\n" : "NOT TAINTED\n");

sub is_tainted
{
  return ! eval {
  join('',@​_), kill 0;
  1;
  };
}
---------------- cut here -----------------------

The above prints "TAINTED" on 5.005_02 and 5.005_03.

It shouldn't.

Interestingly enough, substituting "/yy" for "\Q$pcold\E" fixes
the problem. Why?

Thanks,
-Dave

[p5pRT]

From @rspier

chromatic says​:
#1824 does the right thing on 5.6.0 and 5.8.0.

[p5pRT]

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