Having a look at the source to File::Path it appears, that your code is carping when attempting to perform the unlink. eg.

233                 unless (unlink $root) {
234                     carp "Can't unlink file $root: $!";
235                     if ($force_writeable) {
236                         chmod $rp, $root
237                             or carp("and can't restore permissions
+ to "
238                                     . sprintf("0%o",$rp) . "\n");
239                     }
240                     last;
241                 }
[download]

It might be worth posting a little bit of code to see how you are cleaning up the file name that you are sending to File::Path::rmtree. Also too, have you cleaned up your PATH environment variable prior to the calling of the File::Path::rmtree function?

Ooohhh, Rob no beer function well without!

Hotshot
thanks for your answer. my launder code is :

if ($path =~ /^([-\@\w.\/\s]+)$/) {
   $path = $1;
} else {
   die "Bad path in $path";
}
[download]

and about your suggestion to clean the path, I never had to do this before with perl functions (always with system commands), did you ment soething like that:

$ENV{PATH} = '/usr/lib/perl5/5.6.1/File/';  ?
[download]

thanks

2001-11-19 Edit by Corion : Added formatting

As it is, you find that your data is still tainted after with that regular expression - This is because of the 'valid' parsing of the '/' character by your regular expression. To correctly untaint data, you need to exclude everything except "word" characters (alphabetics, numerics and underscores), hyphens, at characters and a single dot - The inclusion of the forward-slash character allows data to remain tainted because it is exceptionally easy for parsed data to reference files outside the 'permitted scope' of your application - For example, if your routine was supposed to allow the deletion of trees under the directory /home/<user-entered-directory>, a maligned user could easily pervert this code by entering /etc and causing great harm to your system.

The recommended regular expression for untainting data (from perlsec) would be:

if ($data =~ /^([-\@\w.]+)$/) {
    $data = $1;                     # $data now untainted
} else {
    die "Bad data in $data";        # log this somewhere
}
[download]

This may however mean that you will have to modify your code to run under -T and possibly a chroot environment or else you could have potentially nasty users causing harm to your system.

Have a read through the "Laundering and Detecting Tainted Data" and "Cleaning Up Your Path" sections of perlsec.

Update - See davorg's post here for an update on this problem.

 

Ooohhh, Rob no beer function well without!