php-fpm 8.4 crashing if newrelic-daemon is running with ioncube encoded files

[boyinthefog]

Description

When OPcache is enabled and either NewRelic or the zend_test extensions are active, we're seeing a segmentation fault on php files encoded with Ioncube encoder (v13)

Core dump debugging

`
PID: 1353160 (php-fpm8.4)
UID: 1001 (www)
GID: 1001 (www)
Signal: 11 (SEGV)
Timestamp: Mon 2025-07-14 10:22:54 CEST (7min ago)
Command Line: $'php-fpm: pool www-4'
Executable: /usr/sbin/php-fpm8.4
Control Group: /system.slice/php8.4-fpm.service
Unit: php8.4-fpm.service
Slice: system.slice
Boot ID: bea3d0db1016408796f2f0fce1e6c695
Machine ID: 7412f066469c4acb9c386aa7f51c7062
Storage: /var/lib/systemd/coredump/core.php-fpm8\x2e4.1001.bea3d0db1016408796f2f0fce1e6c695.1353160.1752481374000000.zst (present)
Size on Disk: 3.3M
Message: Process 1353160 (php-fpm8.4) of user 1001 dumped core.

            Module libnss_systemd.so.2 from deb systemd-252.38-1~deb12u1.amd64
            Module libsystemd.so.0 from deb systemd-252.38-1~deb12u1.amd64
            Stack trace of thread 1353160:
            #0  0x0000560ade973a89 zend_observer_fcall_begin_prechecked (php-fpm8.4 + 0x3eda89)
            #1  0x0000560ade8fd34e n/a (php-fpm8.4 + 0x37734e)
            #2  0x0000560ade9296b5 execute_ex (php-fpm8.4 + 0x3a36b5)
            #3  0x00007fe4b9af872d n/a (ioncube_loader_lin_8.4.so + 0xf872d)
            #4  0x00007fe4b9afadcf n/a (ioncube_loader_lin_8.4.so + 0xfadcf)
            #5  0x0000560ade6a3bc4 n/a (php-fpm8.4 + 0x11dbc4)
            #6  0x0000560ade6a4630 n/a (php-fpm8.4 + 0x11e630)
            #7  0x00007fe4b9af872d n/a (ioncube_loader_lin_8.4.so + 0xf872d)
            #8  0x00007fe4b9afadcf n/a (ioncube_loader_lin_8.4.so + 0xfadcf)
            #9  0x0000560ade8d81ba zend_call_function (php-fpm8.4 + 0x3521ba)
            #10 0x0000560ade8d85dd zend_call_known_function (php-fpm8.4 + 0x3525dd)
            #11 0x0000560ade774516 n/a (php-fpm8.4 + 0x1ee516)
            #12 0x0000560ade8d73fe zend_lookup_class_ex (php-fpm8.4 + 0x3513fe)
            #13 0x0000560ade8d89e0 zend_fetch_class_by_name (php-fpm8.4 + 0x3529e0)
            #14 0x0000560ade902037 n/a (php-fpm8.4 + 0x37c037)
            #15 0x0000560ade929705 execute_ex (php-fpm8.4 + 0x3a3705)
            #16 0x00007fe4b9af872d n/a (ioncube_loader_lin_8.4.so + 0xf872d)
            #17 0x00007fe4b9afadcf n/a (ioncube_loader_lin_8.4.so + 0xfadcf)
            #18 0x0000560ade8fd5ac n/a (php-fpm8.4 + 0x3775ac)
            #19 0x0000560ade9296b5 execute_ex (php-fpm8.4 + 0x3a36b5)
            #20 0x00007fe4b9af872d n/a (ioncube_loader_lin_8.4.so + 0xf872d)
            #21 0x00007fe4b9afadcf n/a (ioncube_loader_lin_8.4.so + 0xfadcf)
            #22 0x0000560ade927ae5 zend_execute (php-fpm8.4 + 0x3a1ae5)
            #23 0x0000560ade98fa10 zend_execute_script (php-fpm8.4 + 0x409a10)
            #24 0x0000560ade82a5b5 php_execute_script_ex (php-fpm8.4 + 0x2a45b5)
            #25 0x0000560ade6ab96a n/a (php-fpm8.4 + 0x12596a)
            #26 0x00007fe4bcb1a24a n/a (libc.so.6 + 0x2724a)
            #27 0x00007fe4bcb1a305 __libc_start_main (libc.so.6 + 0x27305)
            #28 0x0000560ade6ad941 _start (php-fpm8.4 + 0x127941)
            ELF object binary architecture: AMD x86-64

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Reading symbols from /usr/sbin/php-fpm8.4...
(No debugging symbols found in /usr/sbin/php-fpm8.4)

warning: Can't open file /dev/zero (deleted) during file-backed mapping note processing
[New LWP 1353160]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by php-fpm: pool www-4 '. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x0000560ade973a89 in zend_observer_fcall_begin_prechecked () (gdb)

PHP Version

PHP 8.4.8 (cli) (built: Jun 9 2025 13:42:27) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.4.8, Copyright (c) Zend Technologies
with the ionCube PHP Loader v14.4.1, Copyright (c) 2002-2025, by ionCube Ltd.
with Zend OPcache v8.4.8, Copyright (c), by Zend Technologies

[newrelic-php-agent-bot]

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[ZNeumann]

Thank you for the detailed bug report. Given that the issue persists when using the zend_test observer without the New Relic PHP Agent enabled, this appears to be an upstream issue. I would recommend interacting with php-src (it appears that they have directed you to ioncube as well) and ioncube.