Description
Description
Recurrence condition：
I have an httpd server, its version number is 2.4.54, the working mode is event, in order to prevent the httpd memory from occupying for a long time and not being released, I enabled the httpd-mpm.conf configuration file, and I modified the value of MaxConnectionsPerChild to a specific value, when its value is set to a small value, such as 10, the specific configuration is as follows:
StartServers 5 ServerLimit 10 ThreadLimit 200 MinSpareThreads 75 MaxSpareThreads 250 ThreadsPerChild 25 MaxRequestWorkers 400 MaxConnectionsPerChild 10 MaxClients 250I wrote a simple test case on thinkphp V6.0.12 base framework using PHP 8.1.9，the code is as follows
<?php
namespace app\index\controller;
Class Test
{
public function myTest()
{
$result=file_get_contents("/home/ivstool/version/version.xml");
return json([
"status" => 0,
"resultCode" => 0,
"msg" => 'SUCCESS',
"data" => $result
]
);
}
public function info() {
phpinfo();
}
}
?>
After completing the above basic conditions, I wrote a simple multi-threaded httpd request example using python's multi-threading, the code is as follows：
import requests
import threading
import json
class CoreTest:
def __init__(self):
self.ip ="Server IP address"
requestSession = requests.session()
self.session = requestSession
self.headers = {
'Host': self.ip,
'User-Agent': 'Mozilla/5.0 (Windows NT 6.2; rv:16.0) Gecko/20100101 Firefox/16.0',
'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
'Connection': 'keep-alive',
'referer': "https://{0}".format(self.ip)+":8443/"
}
for i in range(0,100):
self.task('thread_{0}'.format(str(i)))
def task(self, thread_name):
print('I am' + thread_name + 'doing test work....')
url = "https://{0}".format(self.ip)+":8443/index/Test/myTest"
response = self.session.get(url=url, verify=False, headers= self.headers)
print(response.text)
When this use case runs for a period of time, the longer the better, a surprising phenomenon occurs, PHP generates a segmentation fault, I can see that multiple core files are generated in the core dump directory, and I use the GDB tool to trace core file information, get the following stack information
Resulted in this output:
warning: File "/usr/lib64/libthread_db-1.0.so" auto-loading has been declined by your `auto-load safe-path' set to "$debugdir:$datadir/auto-load".
To enable execution of this file add
add-auto-load-safe-path /usr/lib64/libthread_db-1.0.so
line to your configuration file "/root/.gdbinit".
To completely disable this security protection add
set auto-load safe-path /
line to your configuration file "/root/.gdbinit".
For more information about this security protection see the
"Auto-loading safe path" section in the GDB manual. E.g., run from the shell:
info "(gdb)Auto-loading safe path"
warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.
bt
warning: File "/usr/lib64/libthread_db-1.0.so" auto-loading has been declined by your `auto-load safe-path' set to "$debugdir:$datadir/auto-load".
warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.
Core was generated by `/home/ivs_omu_portal/httpd/bin/httpd'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x0000ffffb5a194b8 in zend_signal_handler_defer (signo=1, siginfo=0xffffa2feb610, context=0xffffa2feb690)
at /home/ivs_omu_portal/install/php-src-php-8.1.9/Zend/zend_signal.c:96
96 /home/ivs_omu_portal/install/php-src-php-8.1.9/Zend/zend_signal.c: No such file or directory.
[Current thread is 1 (LWP 1333780)]
(gdb) bt
#0 0x0000ffffb5a194b8 in zend_signal_handler_defer (signo=1, siginfo=0xffffa2feb610, context=0xffffa2feb690)
at /home/ivs_omu_portal/install/php-src-php-8.1.9/Zend/zend_signal.c:96
#1 <signal handler called>
#2 0x0000ffffb6e2dd70 in pthread_kill () from /usr/lib64/libpthread.so.0
#3 0x000000000047641c in wakeup_listener () at event.c:605
#4 0x00000000004764ec in signal_threads (mode=mode@entry=1) at event.c:628
#5 0x000000000047a508 in signal_threads (mode=1) at event.c:619
#6 check_infinite_requests () at event.c:1251
#7 listener_thread (thd=0xffffa2fed1d0, dummy=<optimized out>) at event.c:1679
#8 0x0000ffffb6e267b0 in ?? () from /usr/lib64/libpthread.so.0
#9 0x0000ffffb6d5c23c in ?? () from /usr/lib64/libc.so.6
But I expected this output instead:
no core storage file
PHP Version
PHP-8.1.9
Operating System
Euler