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Unexpected behavior of preg_match #8316
Description
Description
The following code:
<?php
$clean_text = "22ABCDE1ABCDE2ABCDE3ABCDE4ABCDE5ABCDESubtotalABCDE1ABCDE11111ABCDE111111ABCDE22222222222222222222222222222222222ABCDE111111111111111ABCDE211111111111111111111111ABCDE111111111111111111111111ABCDE11111111111111111111111111111ABCDE1111111111ABCDE11111111111111ABCDE11111111111111111111111111111111111111111111111111111";
if( preg_match( '/(.*)ABCDE(.*)ABCDE(.*)ABCDE(.*)ABCDE(.*)ABCDE(.*)ABCDESubtotal/',$clean_text, $data_d ))
print_r($data_d);
else
echo 'NO';Resulted in this output:
NO
But I expected this output instead:
Array
(
[0] => 22ABCDE1ABCDE2ABCDE3ABCDE4ABCDE5ABCDESubtotal
[1] => 22
[2] => 1
[3] => 2
[4] => 3
[5] => 4
[6] => 5
)
If I delete the last char from $clean_text ( or one char from 22222222222222222222222222222222222 ) , preg_match returns TRUE.
I tried on PHP 7.4 and 8.1 , on 2 servers.
PHP Version
PHP 8.1
Operating System
Ubuntu : Linux core 5.3.0-47-generic #39~18.04.1-Ubuntu SMP Mon Apr 6 17:04:32 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
Activity
KapitanOczywisty commentedon Apr 7, 2022
echo preg_last_error_msg();->Backtrack limit exhaustedhttps://www.php.net/manual/en/pcre.configuration.php#ini.pcre.backtrack-limit
Good tool for debugging regex: https://regex101.com/
cmb69 commentedon Apr 7, 2022
Indeed! This is just a bad regex; very quick fix (using ungreedy matching): https://3v4l.org/DJCKD.