Edit report at https://bugs.php.net/bug.php?id=79646&edit=1
ID: 79646
Comment by: enumag at gmail dot com
Reported by: enumag at gmail dot com
Summary: Segmentation fault in garbage collector
Status: Open
Type: Bug
Package: Scripting Engine problem
Operating System: Alpine
PHP Version: 7.4.7
Block user comment: N
Private report: N
New Comment:
@nikic Check this one please.
https://gist.github.com/enumag/329cbe88c5e77c5cc5be74aafa330ba8
Previous Comments:
------------------------------------------------------------------------
[2020-06-15 09:15:18] enumag at gmail dot com
I can use https://github.com/wodby/base-php docker
image for that. Did it before to get the gdb stacktrace. Let me try...
------------------------------------------------------------------------
[2020-06-15 09:04:52] nikic@php.net
Thanks! The first invalid read is:
==182== Invalid read of size 16
==182== at 0xBDF97E1: ???
==182== by 0xA36A9C7: ???
==182== by 0xA36A9C7: ???
==182== by 0xA36A9F2: ???
==182== by 0x4A8312F: ???
==182== by 0xA36A9C7: ???
==182== Address 0xa36a9ef is 63 bytes inside a block of size 72 alloc'd
==182== at 0x489F72A: malloc (vg_replace_malloc.c:309)
==182== by 0x5D30B8: __zend_malloc (in /usr/local/bin/php)
==182== by 0x53ACA6: ??? (in /usr/local/bin/php)
==182== by 0x540AA6: ??? (in /usr/local/bin/php)
==182== by 0x5411E6: ??? (in /usr/local/bin/php)
==182== by 0x67BF73: execute_ex (in /usr/local/bin/php)
==182== by 0x5ED108: zend_call_function (in /usr/local/bin/php)
==182== by 0x617373: zend_call_method (in /usr/local/bin/php)
==182== by 0x4E352A: ??? (in /usr/local/bin/php)
==182== by 0x5ED026: zend_call_function (in /usr/local/bin/php)
==182== by 0x617373: zend_call_method (in /usr/local/bin/php)
==182== by 0x6178BA: zend_user_it_rewind (in /usr/local/bin/php)
Unfortunately most debug symbols are missing, so we don't actually see where the invalid read
occurs :(
Is it possible to install some kind of -dbg / -dbgsym package for PHP on your system?
------------------------------------------------------------------------
[2020-06-15 09:00:39] enumag at gmail dot com
Okay, I ran USE_ZEND_ALLOC=0 valgrind --suppressions=php.supp php vendor/bin/phpunit 2>
valgrind.txt with the php.supp file you provided. Here is the result:
https://gist.github.com/enumag/42402fcc05d9a404656f50a51fb98d2b
Please let me know if it helps.
------------------------------------------------------------------------
[2020-06-15 07:47:41] nikic@php.net
I can't really do anything here without a way to reproduce. GC issues are always tricky, and
"something related to generator GC is broken" is not enough to go on :(
You can try running PHP under valgrind, using something like
USE_ZEND_ALLOC=0 valgrind php ...args
optionally with --suppressions=php.supp from https://gist.github.com/nikic/8d404c6799a1532b0c10280f5e57a888
to reduce noise.
That might give us a better idea of the root cause (which may have nothing to do with GC itself).
------------------------------------------------------------------------
[2020-06-15 06:59:53] enumag at gmail dot com
Unfortunately the segfault persists even with PHP 7.4.7. What should I do now?
------------------------------------------------------------------------
The remainder of the comments for this report are too long. To view
the rest of the comments, please view the bug report online at
https://bugs.php.net/bug.php?id=79646
--
Edit this bug report at https://bugs.php.net/bug.php?id=79646&edit=1