PCRE JIT produces wrong result on ~8192-byte strings

Description

A rather simple anchored pattern produces different results with and without the PCRE JIT when applied to a string just over 8192 characters. The JIT result is wrong.

3v4l.org link

The following code:

<?php

$t = <<<END
(49071,XXXXXXXXXX,XXXXXXXXXX,XXXXXXXXXXXXXXXXXX,XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,0,XXXX,XXXX2XX10X8XXXXXXXXX8XXX02XXXXXX9XXXXXX0XXXX3XXXX8X2XXXXXX7XXXXX,1605115416,XXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX,XXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXX,XXXXX(XXXXXXXXXXXX,XXXXXXX(XXXXX,XXXXXXXXXXXXXX,XXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXX,XXXX(XXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXX,XXXXXXXXXX,XXXXX(XXXXXXXXXXXXXX,XXXX(XXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXX,XXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXXXXXXXX(XXXX(XXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXX(XXXXXXXXXXX,XXXXXXXXXX(XXXXXXXXXXXXXXXXX,XXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXX(XXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXX(XXXXXXX,XXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXX,XXXX(XXXXXXXXXXXXXXXXXXXXXXXXX,XXXXX(XXXXXXXXXXXXX,XXXX(XXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXX,XXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXX,XXXXXXXXXXX,XXXXXXX(XXXXXXXXXXXXX,XXXXXXXXXXX(XXXXXXXXXXXXXXX,XXXXXXX(XXXXXX,XXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXX(XXXXXXXXXXXXX,XXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXX(XXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXXXXX,XXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXX,XXXXXXXXXXXX,XXXXXXXX(XXXXXXXX,XXXXXXXXXXX(XXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXX,XXXXXXXXXXXXXX(XXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXX,XXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXXX,XXXXXXXXXXXXX,XXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXX,XXXXXXXXXX(XXXXXXXXXXX,XXXXXXXXXX(XXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXX,XXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXX,XXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXX,XXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX,XXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX(XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX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END;


$regex = '/\A\((?:[^\\\\\')]|\'(?:[^\'\\\\]|\\\\[\S\s])*?\')*/s';

// test without jit
ini_set("pcre.jit", 0);
echo "length: ", strlen($t), "\n";
echo "match length without pcre.jit: ";
$x = preg_match($regex, $t, $m);
echo ($x ? strlen($m[0]) : "none"), "\n";

// clear PCRE cache
$n = 0;
for ($i = 0; $i < 10000; ++$i) {
    $n += preg_match('/X{' . $i . '}/', $t);
}

// test with jit, should provide same answer
ini_set("pcre.jit", 1);
echo "match length with pcre.jit: ";
$x = preg_match($regex, $t, $m);
echo ($x ? strlen($m[0]) : "none"), "\n";

Resulted in this output:

length: 8220
match length without pcre.jit: 8219
match length with pcre.jit: none

But I expected this output instead:

length: 8220
match length without pcre.jit: 8219
match length with pcre.jit: 8219

PHP Version

PHP 8.0.12 and many others down to 7.3.30

Operating System

Mac OS X, Amazon Linux

Bắt đầu với trình tái hiện PHP được cung cấp và so sánh hai lệnh gọi preg_match khi pcre.jit bị tắt và được bật. Điều tra đường dẫn PCRE JIT chịu trách nhiệm cho các mẫu neo trên các chuỗi chỉ dài hơn 8192 ký tự; hoàn thành có nghĩa là cả hai chế độ đều trả về một kết quả khớp có độ dài 8219.