# [PATCH] str_pad allows pad_length to be negative

- Thread: https://externals.io/message/31152
- Original archive: https://news-web.php.net/php.internals/31152
- Started by Mattias Bengtsson on 2007-07-21T19:57:31+00:00
- Messages: 2
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## #31152 — Mattias Bengtsson — 2007-07-21T19:57:31+00:00

URL: https://externals.io/message/31152#31152

As stated in the manual for `str_pad()` "If the value of pad_length is
negative or less than the length of the input string, no padding takes
place.".

By using a very low negative value it is possible to bypass the check.

Please see attachment.

Cheers, Mattias Bengtsson

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## #31184 — Jani Taskinen — 2007-07-23T13:28:38+00:00

URL: https://externals.io/message/31152#31184 · In reply to: #31152

Patch applied to both PHP_5_2 and HEAD. Thanks!

--Jani



> As stated in the manual for `str_pad()` "If the value of pad_length is
> negative or less than the length of the input string, no padding takes
> place.".
> 
> By using a very low negative value it is possible to bypass the check.
> 
> Please see attachment.
> 
> Cheers, Mattias Bengtsson