Bug #79194 [Com]: Segmentation fault

Edit report at https://bugs.php.net/bug.php?id=79194&edit=1 ID: 79194 Comment by: benjamin dot morel at gmail dot com Reported by: benjamin dot morel at gmail dot com Summary: Segmentation fault Status: Open Type: Bug Package: Reproducible crash Operating System: Fedora 31 PHP Version: 7.4.2 Block user comment: N Private report: N New Comment: OK, adding breakpoints to the generated Twig view made me find the error: a memory exhaustion due to a recursive function call in an entity: public function isSubscribed() : bool { return $this->isSubscribed(); } Instead of: return $this->isSubscribed; Now, a few questions remain: - I'm surprised I didn't get a line in the php-fpm error log; is this expected in this case? - I guess the segfault occurring when memory is exhausted is a bug; should I file a bug with Blackfire? Previous Comments: ------------------------------------------------------------------------ [2020-01-29 22:54:04] benjamin dot morel at gmail dot com Description: ------------ I'm experiencing a segfault occurring during the rendering of a Twig template in a Symfony app. I pinpointed it to the blackfire extension: php-fpm[4131]: segfault at 7ffd4502efd8 ip 00007f7ea5fdc6d1 sp 00007ffd4502efe0 error 6 in blackfire-20190902.so[7f7ea5fc4000+5f000] I originally thought I'd report the bug with Blackfire, but I think there's more to it: when I disable the blackfire extension, I get no segfault anymore, but I receive a white page (Symfony in prod mode) or a partial HTML page (dev mode) after 10 seconds, without any error in the PHP-FPM logs. gdb output for the segfault: (only showing the first 10 entries, it goes on and on for more than 20000 entries—there may be many more, I gave up after that) Reading symbols from /usr/sbin/php-fpm... Reading symbols from /usr/lib/debug/usr/sbin/php-fpm-7.4.2-1.fc31.remi.x86_64.debug... [New LWP 4132] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". Core was generated by `php-fpm: pool www '. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x00007f7ea5fdc6d1 in bf_zend_execute () from /usr/lib64/php/modules/blackfire.so (gdb) bt #0 0x00007f7ea5fdc6d1 in bf_zend_execute () from /usr/lib64/php/modules/blackfire.so #1 0x0000560bec0b20c0 in ZEND_DO_FCALL_SPEC_RETVAL_USED_HANDLER () at /usr/src/debug/php-7.4.2-1.fc31.remi.x86_64/Zend/zend_vm_execute.h:1714 #2 execute_ex (ex=0x7f7e99d6b2c0) at /usr/src/debug/php-7.4.2-1.fc31.remi.x86_64/Zend/zend_vm_execute.h:53821 #3 0x00007f7ea5fdc6f8 in bf_zend_execute () from /usr/lib64/php/modules/blackfire.so #4 0x0000560bec0b20c0 in ZEND_DO_FCALL_SPEC_RETVAL_USED_HANDLER () at /usr/src/debug/php-7.4.2-1.fc31.remi.x86_64/Zend/zend_vm_execute.h:1714 #5 execute_ex (ex=0x7f7e99d6b2c0) at /usr/src/debug/php-7.4.2-1.fc31.remi.x86_64/Zend/zend_vm_execute.h:53821 #6 0x00007f7ea5fdc6f8 in bf_zend_execute () from /usr/lib64/php/modules/blackfire.so #7 0x0000560bec0b20c0 in ZEND_DO_FCALL_SPEC_RETVAL_USED_HANDLER () at /usr/src/debug/php-7.4.2-1.fc31.remi.x86_64/Zend/zend_vm_execute.h:1714 #8 execute_ex (ex=0x7f7e99d6b2c0) at /usr/src/debug/php-7.4.2-1.fc31.remi.x86_64/Zend/zend_vm_execute.h:53821 #9 0x00007f7ea5fdc6f8 in bf_zend_execute () from /usr/lib64/php/modules/blackfire.so #10 0x0000560bec0b20c0 in ZEND_DO_FCALL_SPEC_RETVAL_USED_HANDLER () at /usr/src/debug/php-7.4.2-1.fc31.remi.x86_64/Zend/zend_vm_execute.h:1714 Not sure how I can further detail the bug, please let me know what you need! ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=79194&edit=1