in reply to unlink taint

It's not the wildcard (.*) that makes the expression tainted, but rather what's in $upload_dir and/or $in{'imgid'} (if they originate from program-external input), so you need to untaint those. update: actually, it's the glob itself that, too, returns tainted data (with or without '*').

See perlsec for how to do it.

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Re^2: unlink taint
by ikegami (Patriarch) on Dec 20, 2010 at 22:06 UTC

    You are mistaken. 

    $ perl -MScalar::Util=tainted -TE'say tainted($_) for glob "*"'
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    glob is a source of external input when "*" is used. Same goes for readdir. 

    $ perl -MScalar::Util=tainted -TE'opendir(my $dh, "."); say tainted($_
+) for readdir($dh)'
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[d/l]
[select]
      glob is a source of external input when "*" is used.

      You're right. A quick test shows, though, that it doesn't matter whether there's a '*' in the glob expression or not: 

      $ perl -MScalar::Util=tainted -TE'say tainted($_) for glob "foo"'
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[d/l]
        Interesting, thanks.
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Re^2: unlink taint
by toniax (Scribe) on Dec 20, 2010 at 21:52 UTC
    I tried to untaint $upload_dir and/or $in{'imgid'} and it did not work . I will have to read up on it more Thanks
    -X-
[reply]
      How did you try to untaint those values, and how did you determine that it did not work?
[reply]

      If you show the code you've tried, we might see what was wrong with it...

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