[perl #122424] Unicode::Collate gives incorrect cmp() values for tainted strings

# New Ticket Created by  Philip Boulain 
# Please include the string:  [perl #122424]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=122424 >


This is a bug report for perl from philip.boulain@smoothwall.net,
generated with the help of perlbug 1.39 running under perl 5.14.2.


-----------------------------------------------------------------
[Please describe your issue here]

Unicode::Collate's cmp() always returns zero when comparing
tainted strings. getSortKey() seems to always return a minimal
string for them.

You can test this with a simple one-liner:

$ perl -T -MScalar::Util -MUnicode::Collate -Mstrict -w -e 'my $x =
<STDIN>; my $y = <STDIN>; print Scalar::Util::tainted($x) ? "x tainted\n" :
"x not tainted\n"; print Unicode::Collate->new()->cmp($x, $y); print "\n";';
a
b
x tainted
0

(Type the 'a' and 'b'.)

If you remove the -T option, you get the expected output:

x not tainted
-1

There does not appear to be any documentation on
Unicode::Collate's behaviour in taint mode.

[Please do not change anything below this line]
-----------------------------------------------------------------
---
Flags:
    category=library
    severity=medium
    module=Unicode::Collate
---
Site configuration information for perl 5.14.2:

Configured by Debian Project at Tue Feb  4 23:09:53 UTC 2014.

Summary of my perl5 (revision 5 version 14 subversion 2) configuration:

  Platform:
    osname=linux, osvers=2.6.42-37-generic,
archname=x86_64-linux-gnu-thread-multi
    uname='linux panlong 2.6.42-37-generic #58-ubuntu smp thu jan 24
15:28:10 utc 2013 x86_64 x86_64 x86_64 gnulinux '
    config_args='-Dusethreads -Duselargefiles -Dccflags=-DDEBIAN
-Dcccdlflags=-fPIC -Darchname=x86_64-linux-gnu -Dprefix=/usr
-Dprivlib=/usr/share/perl/5.14 -Darchlib=/usr/lib/perl/5.14
-Dvendorprefix=/usr -Dvendorlib=/usr/share/perl5
-Dvendorarch=/usr/lib/perl5 -Dsiteprefix=/usr/local
-Dsitelib=/usr/local/share/perl/5.14.2
-Dsitearch=/usr/local/lib/perl/5.14.2 -Dman1dir=/usr/share/man/man1
-Dman3dir=/usr/share/man/man3 -Dsiteman1dir=/usr/local/man/man1
-Dsiteman3dir=/usr/local/man/man3 -Duse64bitint -Dman1ext=1 -Dman3ext=3perl
-Dpager=/usr/bin/sensible-pager -Uafs -Ud_csh -Ud_ualarm -Uusesfio -Uusenm
-Ui_libutil -DDEBUGGING=-g -Doptimize=-O2 -Duseshrplib
-Dlibperl=libperl.so.5.14.2 -des'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=define, usemultiplicity=define
    useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
    use64bitint=define, use64bitall=define, uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN
-fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include
-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O2 -g',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fno-strict-aliasing
-pipe -fstack-protector -I/usr/local/include'
    ccversion='', gccversion='4.6.3', gccosandvers=''
    intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t',
lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -fstack-protector -L/usr/local/lib'
    libpth=/usr/local/lib /lib/x86_64-linux-gnu /lib/../lib
/usr/lib/x86_64-linux-gnu /usr/lib/../lib /lib /usr/lib
    libs=-lgdbm -lgdbm_compat -ldb -ldl -lm -lpthread -lc -lcrypt
    perllibs=-ldl -lm -lpthread -lc -lcrypt
    libc=, so=so, useshrplib=true, libperl=libperl.so.5.14.2
    gnulibc_version='2.15'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -O2 -g -L/usr/local/lib
-fstack-protector'

Locally applied patches:


---
@INC for perl 5.14.2:
    /etc/perl
    /usr/local/lib/perl/5.14.2
    /usr/local/share/perl/5.14.2
    /usr/lib/perl5
    /usr/share/perl5
    /usr/lib/perl/5.14
    /usr/share/perl/5.14
    /usr/local/lib/site_perl
    .

---
Environment for perl 5.14.2:
    HOME=/home/philip
    LANG=en_GB.UTF-8
    LANGUAGE=en_GB:en
    LD_LIBRARY_PATH=/home/philip/opt/lib:
    LOGDIR (unset)

PATH=/home/philip/opt/bin:/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
    PERL_BADLANG (unset)
    SHELL=/bin/bash

-- 
Dr. Philip Boulain
Developer
philip.boulain@smoothwall.net

Smoothwall Ltd
Phone: +44 (0) 8701 999500
www.smoothwall.net

Smoothwall Limited is registered in England, Company Number: 4298247 and
whose registered address is 1 John Charles Way, Leeds, LS12 6QA United
Kingdom
Any opinions stated in this message are solely those of the author.

• [perl #122424] Unicode::Collate gives incorrect cmp() values for tainted strings by Philip Boulain
• Re: [perl #122424] Unicode::Collate gives incorrect cmp() valuesfor tainted strings by Karl Williamson