Thanks, your explanation does help. However it seems that in my example $foo is not tainted, (its value is "HASH(0x80f8a20)") - only the values of the hash reference are tainted (%$foo has become dirty because the value of one of the keys was bad). I think you knew this.

Your explanation does mean I can push the tainted data down a level to clean up my hash-ref, eg: 
  $dirty{text} = <>;
  $foo = {
        'clean'         => '/home/boldra/filename.txt',
        'dirty'         => \%dirty,
  };
  open(F,"+>{$foo->{clean}}");
  close(F);

[download]
Which leaves $foo->{clean} clean as a whistle.

But I still don't see why I have to do this. Is it because taint checking is simply clumsy, or is there actually a risk of a user supplying data that perl will accidentally interprect as the boundry between two values in an array?

What I'm worrying about is: Is $foo->{clean} really tainted (in my original example) or is it a false positive by the taint-checking? If it's really tainted - what sort of cleaning does it need?

Thanks,

- Boldra

In reply to Re: Re: tainted entangled hashrefs by Boldra
in thread tainted entangled hashrefs by Boldra

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