UBSan abort in ext/gd/libgd/gd_interpolation.c:1007

[YuanchengJiang]

Description

The following code:

<?php
$input = imagecreatefrompng(__DIR__ . '/gh10614.png');
for ($angle = 0; $angle <= 270; $angle += 90) {
$output = imagerotate($input, $angle, 0);
}
$fusion = $output;
$thumbnail = imagescale($fusion, -1, 64, IMG_BICUBIC);

Resulted in this output:

/php-src/ext/gd/libgd/gd_interpolation.c:1007:28: runtime error: left shift of 134 by 24 places cannot be represented in type 'int'

PHP Version

nightly

Operating System

ubuntu 22.04

[nielsdos]

Right, alpha must be 0x7f at most; uchar_clamp in upstream takes an extra argument but we don't...