msgpack (un)pack error

[a4blue]

As attachment i have an object which produces following Warning:
(msgpack_unserialize_map_item) Invalid references value: 29696
This Behaviour was tested and reproduced under following conditions:
php_only was set to true,
php7.4 with msgpack-master
php7.4 with msgpack 2.0.3
php7.4 with msgpack 2.1.0
php 7.2 with msgpack 2.0.2

simple script to reproduce:

<?php
$data=unserialize(file_get_contents('php_serialized.txt));
// echo is empty and msgpack issues a warning 
// there should be no warning and echo should print 1
echo $data == msgpack_unpack(msgpack_pack($data)));

Any help on how to debug this would be appreciated
php_serialized.txt

[m6w6]

Hi! Thank you for your report. We'll look into it.

[andypost]

Just get the test failure when packaged 2.2.0RC1 for Alpinelinux, btw restart of test helped and it passed

The failure https://gitlab.alpinelinux.org/alpine/aports/-/jobs/474442#L510

PHP : /usr/bin/php7 
PHP_SAPI : cli
PHP_VERSION : 7.4.23
ZEND_VERSION: 3.4.0
PHP_OS : Linux - Linux runner-xdqdyyub-project-1-concurrent-0 5.10.7-0-lts #1-Alpine SMP Thu, 14 Jan 2021 07:31:13 UTC i686
INI actual : /builds/alpine/aports/community/php7-pecl-msgpack/src/msgpack-2.2.0RC1/tmp-php.ini
More .INIs : 
CWD : /builds/alpine/aports/community/php7-pecl-msgpack/src/msgpack-2.2.0RC1
Extra dirs : 
VALGRIND : Not used
=====================================================================
TIME START 2021-08-30 19:47:10
....
TEST 135/135 [tests/issue149.phpt]
========DIFF========
002+ bool(false)
002- bool(true)
========DONE========
FAIL Issue #149 (msgpack (un)pack error with serialize()) [tests/issue149.phpt] 

[m6w6]

@andypost Do you mean it once failed, and then passed?

[andypost]

Yes, it randomly fails (only on x86 arch) both 7.4 and 8.0

[m6w6]

Oh 🤦 x86! Any idea where I could easily test against that?

[andypost]

Here's a way to reproduce

$ make -f AMakefile x86
...docker download image and run it mounting source code

...inside container
$ make -f AMakefile provision -B
...
$ make clean && make

... repeat next until diff is broken
$ make -f AMakefile test

@m6w6 you could use sudo apk add gdb or whatever tool you need from https://pkgs.alpinelinux.org/packages

Here's a AMakefile and test-dubug.patch and few *.diff of data vs check objects, see attached

test-debug.tar.gz

[andypost]

Also you can replace php8 with php7 package

[m6w6]

Awesome, I'll give it a go, thanks!

[andypost]

FYI just caught the same test fail on armhf which is 32-bit as well

[m6w6]

Looks like a hash collision, apparently existing since forever on 32bit.
https://github.com/msgpack/msgpack-php/blob/master/msgpack_pack.c#L51

[andypost]

Sounds like better to disable for 32-bit arches for a while