SEGV Zend/zend_alloc.c

[YuanchengJiang]

Description

The following code:

<?php
function setStyleAndThickness($im, $color, $thickness)
{
while ($i < 16 * $thickness) {
$style[$i++] = $color;
}
}
$im = imagecreate(800, 800);
setStyleAndThickness($im, $black, 6);
imagepalettetotruecolor($im);

Resulted in this output:

/home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_alloc.c:1528:35: runtime error: member access within null pointer of type 'zend_mm_chunk' (aka 'struct _zend_mm_chunk')
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_alloc.c:1528:35 in 

To reproduce:

-d "memory_limit=2M"

Commit:

commit 2acda557cd83fd72bc8dbe3756d29dbe779f7249
Author: Niels Dossche <7771979+nielsdos@users.noreply.github.com>
Date:   Mon Feb 10 08:43:35 2025 +0100

    Pack _php_sqlite3_db_object

Configurations:

CC="clang-12" CXX="clang++-12" CFLAGS="-DZEND_VERIFY_TYPE_INFERENCE" CXXFLAGS="-DZEND_VERIFY_TYPE_INFERENCE" ./configure --enable-debug --enable-address-sanitizer --enable-undefined-sanitizer --enable-re2c-cgoto --enable-fpm --enable-litespeed --enable-phpdbg-debug --enable-zts --enable-bcmath --enable-calendar --enable-dba --enable-dl-test --enable-exif --enable-ftp --enable-gd --enable-gd-jis-conv --enable-mbstring --enable-pcntl --enable-shmop --enable-soap --enable-sockets --enable-sysvmsg --enable-zend-test --with-zlib --with-bz2 --with-curl --with-enchant --with-gettext --with-gmp --with-mhash --with-ldap --with-libedit --with-readline --with-snmp --with-sodium --with-xsl --with-zip

Operating System:

Ubuntu 20.04 Host, Docker 0599jiangyc/flowfusion:latest

This report is automatically generated by FlowFusion

PHP Version

2acda55

Operating System

No response

[devnexen]

One of the tpixels get corrupted, gd frees invalid address. Will have a look later.