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Accessing a BcMath\Number property by ref crashes #18641

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Description

@YuanchengJiang

Description

The following code:

<?php
$a = new BCMath\Number("1");
$fusion = $a;
Test::$test = &$fusion->value;

Resulted in this output:

/home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_types.h:670:13: runtime error: member access within misaligned address 0x7e5313a4b3d7 for type 'const zval' (aka 'const struct _zval_struct'), which requires 8 byte alignment
0x7e5313a4b3d7: note: pointer points here
<memory cannot be printed>
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_types.h:670:13 in 

To reproduce:

./php-src/sapi/cli/php  ./test.php

Commit:

dfff6ac852a23c6e33c06c7716d095ad4a7166d8

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 --with-mysqli --with-pdo-mysql --with-pdo-pgsql --with-pgsql --with-sqlite3 --with-pdo-sqlite --with-webp --with-jpeg --with-freetype --enable-sigchild --with-readline --with-pcre-jit --with-iconv

Operating System:

Ubuntu 20.04 Host, Docker 0599jiangyc/flowfusion:latest

This report is automatically generated by FlowFusion

PHP Version

dfff6ac852a23c6e33c06c7716d095ad4a7166d8

Operating System

No response

Activity

  1. self-assigned this
    on May 24, 2025
  2. changed the title [-]SEGV Zend/zend_types.h[/-] [+]Accessing a BcMath\Number property by ref crashes[/+] on May 24, 2025
  3. added a commit that references this issue on May 24, 2025
    8fa745e
  4. added a commit that references this issue on May 24, 2025
    64d511e
  5. added a commit that references this issue on May 24, 2025
    25e60d6
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