TMPVAR object with hook creating a self-reference leaks

[nielsdos]

Description

The following code:

<?php

class Foo {
    public $prop { get {
        $this->prop = $this;
        return $this;
    }}
}

(new Foo)->prop;

Resulted in this output:

=================================================================
==706473==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 56 byte(s) in 1 object(s) allocated from:
    #0 0x7f3c37120e15 in malloc /usr/src/debug/gcc/gcc/libsanitizer/asan/asan_malloc_linux.cpp:67
    #1 0x556f537019ed in __zend_malloc /run/media/niels/MoreData/php-src/Zend/zend_alloc.c:3518
    #2 0x556f536fd981 in _emalloc /run/media/niels/MoreData/php-src/Zend/zend_alloc.c:2762
    #3 0x556f53aad029 in zend_objects_new /run/media/niels/MoreData/php-src/Zend/zend_objects.c:210
    #4 0x556f537149d4 in _object_and_properties_init /run/media/niels/MoreData/php-src/Zend/zend_API.c:1828
    #5 0x556f53714b86 in object_init_ex /run/media/niels/MoreData/php-src/Zend/zend_API.c:1851
    #6 0x556f5387e5bb in ZEND_NEW_SPEC_CONST_UNUSED_HANDLER /run/media/niels/MoreData/php-src/Zend/zend_vm_execute.h:11042
    #7 0x556f539a00f4 in execute_ex /run/media/niels/MoreData/php-src/Zend/zend_vm_execute.h:60061
    #8 0x556f539afa32 in zend_execute /run/media/niels/MoreData/php-src/Zend/zend_vm_execute.h:64385
    #9 0x556f53b158b9 in zend_execute_script /run/media/niels/MoreData/php-src/Zend/zend.c:1943
    #10 0x556f5354ffb0 in php_execute_script_ex /run/media/niels/MoreData/php-src/main/main.c:2594
    #11 0x556f535503b8 in php_execute_script /run/media/niels/MoreData/php-src/main/main.c:2634
    #12 0x556f53b1b5c8 in do_cli /run/media/niels/MoreData/php-src/sapi/cli/php_cli.c:952
    #13 0x556f53b1dc1a in main /run/media/niels/MoreData/php-src/sapi/cli/php_cli.c:1363
    #14 0x7f3c36b886b4  (/usr/lib/libc.so.6+0x276b4) (BuildId: 468e3585c794491a48ea75fceb9e4d6b1464fc35)
    #15 0x7f3c36b88768 in __libc_start_main (/usr/lib/libc.so.6+0x27768) (BuildId: 468e3585c794491a48ea75fceb9e4d6b1464fc35)
    #16 0x556f52a03fb4 in _start (/run/media/niels/MoreData/php-src/sapi/cli/php+0x603fb4) (BuildId: 2a1a4f16068276f3efa4ba67d81c1a989371a979)

But I expected this output instead:

no leak

PHP Version

8.4+

Operating System

No response

[YuanchengJiang]

I have many leaks, any insight to filter interesting ones?

[iluuu1994]

@YuanchengJiang Can you show an example? Most leaks should be legitimate, given that we use the long jump mechanism on fatal error to perform a proper shutdown.

[YuanchengJiang]

Sure.

The following code:

<?php
function &cb() {
}
$file = __DIR__ . '/gh18439.zip';
$zip = new ZipArchive;
$zip->open($file, ZIPARCHIVE::CREATE);
$zip->registerCancelCallback(cb(...));
$zip->addFromString('test', 'test');
$fusion = $zip;

Resulted in this output:

=================================================================
==785487==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 14 byte(s) in 1 object(s) allocated from:
    #0 0x66cd04 in strdup (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x66cd04)
    #1 0x58e7089 in do_cli /home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php_cli.c:892:24
    #2 0x58e327f in main /home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php_cli.c:1363:18
    #3 0x752705395d8f in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16

Direct leak of 8 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055c26f9 in zip_close (/lib/x86_64-linux-gnu/libzip.so.4+0xd6f9)
    #2 0x57670b1 in zend_objects_store_del /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_objects_API.c:196:4
    #3 0x5879597 in rc_dtor_func /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_variables.c:57:2
    #4 0x587981e in i_zval_ptr_dtor /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_variables.h:45:4
    #5 0x58795d4 in zval_ptr_dtor /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_variables.c:84:2
    #6 0x53a4e01 in _zend_hash_del_el_ex /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_hash.c:1486:3
    #7 0x53a257d in _zend_hash_del_el /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_hash.c:1513:2
    #8 0x53b7916 in zend_hash_graceful_reverse_destroy /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_hash.c:2038:4
    #9 0x4aca9d2 in zend_shutdown_executor_values /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_execute_API.c:285:3
    #10 0x4ad70be in shutdown_executor /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_execute_API.c:449:2
    #11 0x58c2b1b in zend_deactivate /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend.c:1350:2
    #12 0x40b4495 in php_request_shutdown /home/phpfuzz/WorkSpace/flowfusion/php-src/main/main.c:1969:2
    #13 0x58ee2a1 in do_cli /home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php_cli.c:1159:3
    #14 0x58e327f in main /home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php_cli.c:1363:18
    #15 0x752705395d8f in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16

Indirect leak of 2048 byte(s) in 1 object(s) allocated from:
    #0 0x6811e2 in calloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x6811e2)
    #1 0x7527055bc8d0  (/lib/x86_64-linux-gnu/libzip.so.4+0x78d0)

Indirect leak of 512 byte(s) in 1 object(s) allocated from:
    #0 0x681389 in realloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x681389)
    #1 0x7527055bd68d  (/lib/x86_64-linux-gnu/libzip.so.4+0x868d)

Indirect leak of 200 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055c87d1  (/lib/x86_64-linux-gnu/libzip.so.4+0x137d1)

Indirect leak of 160 byte(s) in 2 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055c8477  (/lib/x86_64-linux-gnu/libzip.so.4+0x13477)

Indirect leak of 128 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055bb64b  (/lib/x86_64-linux-gnu/libzip.so.4+0x664b)

Indirect leak of 120 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055ba52d  (/lib/x86_64-linux-gnu/libzip.so.4+0x552d)

Indirect leak of 88 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055bdad9 in zip_register_cancel_callback_with_state (/lib/x86_64-linux-gnu/libzip.so.4+0x8ad9)

Indirect leak of 80 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055bb7dc  (/lib/x86_64-linux-gnu/libzip.so.4+0x67dc)

Indirect leak of 64 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055c509b  (/lib/x86_64-linux-gnu/libzip.so.4+0x1009b)
    #2 0x4e1a01b in ZEND_DO_FCALL_SPEC_RETVAL_UNUSED_HANDLER /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_vm_execute.h:1992:4
    #3 0x4b5cc73 in execute_ex /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_vm_execute.h:58696:12
    #4 0x4b5f1fc in zend_execute /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_vm_execute.h:64385:2
    #5 0x58d3f89 in zend_execute_script /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend.c:1943:3
    #6 0x40c77ba in php_execute_script_ex /home/phpfuzz/WorkSpace/flowfusion/php-src/main/main.c:2594:13
    #7 0x40c88f8 in php_execute_script /home/phpfuzz/WorkSpace/flowfusion/php-src/main/main.c:2634:9
    #8 0x58e8e9a in do_cli /home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php_cli.c:952:5
    #9 0x58e327f in main /home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php_cli.c:1363:18
    #10 0x752705395d8f in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16

Indirect leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055bcad1  (/lib/x86_64-linux-gnu/libzip.so.4+0x7ad1)

Indirect leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055c719e  (/lib/x86_64-linux-gnu/libzip.so.4+0x1219e)

Indirect leak of 24 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055bb661  (/lib/x86_64-linux-gnu/libzip.so.4+0x6661)

Indirect leak of 24 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055c74df  (/lib/x86_64-linux-gnu/libzip.so.4+0x124df)

Indirect leak of 17 byte(s) in 1 object(s) allocated from:
    #0 0x66cd04 in strdup (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x66cd04)
    #1 0x7527055c880f  (/lib/x86_64-linux-gnu/libzip.so.4+0x1380f)

Indirect leak of 16 byte(s) in 1 object(s) allocated from:
    #0 0x681389 in realloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x681389)
    #1 0x7527055bb791  (/lib/x86_64-linux-gnu/libzip.so.4+0x6791)

Indirect leak of 16 byte(s) in 1 object(s) allocated from:
    #0 0x681389 in realloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x681389)
    #1 0x7527055bb778  (/lib/x86_64-linux-gnu/libzip.so.4+0x6778)

Indirect leak of 5 byte(s) in 1 object(s) allocated from:
    #0 0x68106d in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x68106d)
    #1 0x7527055c71b7  (/lib/x86_64-linux-gnu/libzip.so.4+0x121b7)

SUMMARY: AddressSanitizer: 3596 byte(s) leaked in 20 allocation(s).

To reproduce:

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

Commit:

e9310171f767d95c34df90eebfbec7d61ad22bbc

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

Any magic I can do to find legitimate leaks?