|  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login
Bug #68001 php crashes with enabled php_snmp.dll
Submitted: 2014-09-10 17:50 UTC Modified: 2014-10-04 12:27 UTC
From: xbolshe at mail dot ru Assigned:
Status: Not a bug Package: SNMP related
PHP Version: 5.6.0 OS: Windows 2008 R2
Private report: No CVE-ID: None
 [2014-09-10 17:50 UTC] xbolshe at mail dot ru
PHP crashes with enabled php_snmp.dll with or without lauched Apache HTTPD (command like php -version).

Faulting application name: php.exe, version:, time stamp: 0x53fe29da
Faulting module name: php_snmp.dll, version:, time stamp: 0x53fe2c15
Exception code: 0xc0000409
Fault offset: 0x00042085
Faulting process id: 0xa70
Faulting application start time: 0x01cfcd1d08a2994b
Faulting application path: d:\php\php.exe
Faulting module path: d:\php\ext\php_snmp.dll
Report Id: 46884532-3910-11e4-8a3c-a0481cb82cc1


Probably need to check /GS option of VC11 compiler.


Add a Patch

Pull Requests

Add a Pull Request


AllCommentsChangesGit/SVN commitsRelated reports
 [2014-09-10 18:53 UTC] xbolshe at mail dot ru
Microsoft (R) Windows Debugger Version 6.3.9600.17200 X86
Copyright (c) Microsoft Corporation. All rights reserved.

CommandLine: D:\php\php.exe
Symbol search path is: *** Invalid ***
* Symbol loading may be unreliable without a symbol search path.           *
* Use .symfix to have the debugger choose a symbol path.                   *
* After setting your symbol path, use .reload to refresh symbol locations. *
Executable search path is: 
ModLoad: 000d0000 000e4000   php.exe 
ModLoad: 77c60000 77de0000   ntdll.dll
ModLoad: 770a0000 771b0000   C:\Windows\syswow64\kernel32.dll
ModLoad: 77810000 77857000   C:\Windows\syswow64\KERNELBASE.dll
ModLoad: 651a0000 65804000   D:\php\php5ts.dll
ModLoad: 769e0000 76a80000   C:\Windows\syswow64\ADVAPI32.dll
ModLoad: 771b0000 7725c000   C:\Windows\syswow64\msvcrt.dll
ModLoad: 77260000 77279000   C:\Windows\SysWOW64\sechost.dll
ModLoad: 76c80000 76d70000   C:\Windows\syswow64\RPCRT4.dll
ModLoad: 75650000 756b0000   C:\Windows\syswow64\SspiCli.dll
ModLoad: 75640000 7564c000   C:\Windows\syswow64\CRYPTBASE.dll
ModLoad: 77060000 77095000   C:\Windows\syswow64\WS2_32.dll
ModLoad: 75bd0000 75bd6000   C:\Windows\syswow64\NSI.dll
ModLoad: 66310000 6639c000   C:\Windows\SysWOW64\ODBC32.dll
ModLoad: 774e0000 775e0000   C:\Windows\syswow64\USER32.dll
ModLoad: 75a10000 75aa0000   C:\Windows\syswow64\GDI32.dll
ModLoad: 77c30000 77c3a000   C:\Windows\syswow64\LPK.dll
ModLoad: 76920000 769bd000   C:\Windows\syswow64\USP10.dll
ModLoad: 758b0000 75a0c000   C:\Windows\syswow64\ole32.dll
ModLoad: 751f0000 75234000   C:\Windows\SysWOW64\DNSAPI.dll
ModLoad: 650c0000 65196000   C:\Windows\SysWOW64\MSVCR110.dll
(450.25c): Break instruction exception - code 80000003 (first chance)
*** ERROR: Symbol file could not be found.  Defaulted to export symbols for ntdll.dll - 
eax=00000000 ebx=00000000 ecx=afb60000 edx=001be028 esi=fffffffe edi=00000000
eip=77d0103b esp=00b5f4c0 ebp=00b5f4ec iopl=0         nv up ei pl zr na pe nc
cs=0023  ss=002b  ds=002b  es=002b  fs=0053  gs=002b             efl=00000246
77d0103b cc              int     3

0:000> !analyze -v
*                                                                             *
*                        Exception Analysis                                   *
*                                                                             *

77d0103b cc              int     3

EXCEPTION_RECORD:  ffffffff -- (.exr 0xffffffffffffffff)
ExceptionAddress: 77d0103b (ntdll!LdrpDoDebuggerBreak+0x0000002c)
   ExceptionCode: 80000003 (Break instruction exception)
  ExceptionFlags: 00000000
NumberParameters: 1
   Parameter[0]: 00000000

CONTEXT:  00000000 -- (.cxr 0x0;r)
eax=00000000 ebx=00000000 ecx=afb60000 edx=001be028 esi=fffffffe edi=00000000
eip=77d0103b esp=00b5f4c0 ebp=00b5f4ec iopl=0         nv up ei pl zr na pe nc
cs=0023  ss=002b  ds=002b  es=002b  fs=0053  gs=002b             efl=00000246
77d0103b cc              int     3


PROCESS_NAME:  php.exe

ERROR_CODE: (NTSTATUS) 0x80000003 - {EXCEPTION}  Breakpoint  A breakpoint has been reached.

EXCEPTION_CODE: (HRESULT) 0x80000003 (2147483651) - One or more arguments are invalid




APP:  php.exe

ANALYSIS_VERSION: 6.3.9600.17237 (debuggers(dbg).140716-0327) x86fre

ADDITIONAL_DEBUG_TEXT:  Followup set based on attribute [OsBuildNumber] from Frame:[ffffffff] on thread:[PSEUDO_THREAD] ; Followup set based on attribute [Is_ChosenCrashFollowupThread] from Frame:[0] on thread:[PSEUDO_THREAD]

LAST_CONTROL_TRANSFER:  from 77ce13d3 to 77d0103b




00000000 00000000 php.exe!Unknown+0x0


SYMBOL_NAME:  php.exe!Unknown

FOLLOWUP_NAME:  MachineOwner


IMAGE_NAME:  php.exe


STACK_COMMAND:  dt ntdll!LdrpLastDllInitializer BaseDllName ; dt ntdll!LdrpFailureData ; ** Pseudo Context ** ; kb

FAILURE_BUCKET_ID:  LOADER_INIT_FAILURE_80000003_80000003_php.exe!Unknown



FAILURE_ID_HASH_STRING:  um:loader_init_failure_80000003_80000003_php.exe!unknown

FAILURE_ID_HASH:  {67b205bf-3cd0-c31b-c123-f975196730a5}

Followup: MachineOwner
 [2014-09-11 05:23 UTC] xbolshe at mail dot ru
See a picture:
As shown on the picture int 3 CPU command is executed as a reason of stack buffer overrun and cause an exception shown previously. It seems that stack buffer size is not enough. 

A possible reason of this problem may be usage of char strings with fixed size which are overrun. I guess need to to check buffers in /php-src/ext/snmp/snmp.c
 [2014-09-12 19:20 UTC] xbolshe at mail dot ru
I have found a point of crash: when php.exe(php_snmp.dll) searches for c:\usr\snmp\persist\mib_indexes\ and finds two files with names "0" and "1", it crashes. After deleting of these files "0" and "1" the problem is disappeared.
 [2014-09-12 21:14 UTC] xbolshe at mail dot ru
I have repeated the problem with my build of PHP.
The PHP crash is performed here:

File: php-src\ext\snmp\snmp.c 

	netsnmp_log_handler *logh;
	zend_class_entry ce, cex;

	le_snmp_session = zend_register_list_destructors_ex(php_snmp_session_destructor, NULL, PHP_SNMP_SESSION_RES_NAME, module_number);
	init_snmp("snmpapp");       <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< HERE
 [2014-09-12 22:11 UTC]
-Status: Open +Status: Feedback
 [2014-09-12 22:11 UTC]
This is an issue in net-snmp outside our control. Please report at
 [2014-09-12 23:20 UTC] xbolshe at mail dot ru
Partially agree with you. 

1. Crashing of PHP may be fixed. A SEH handler installation for "init_snmp("snmpapp");" with writing a PHP log about trouble with Net-SNMP and possible ways to fix like re-installation of Net-SNMP, removing MIB indexes will make PHP more user friendly.

2. The main reason of my trouble was that one MIB index file was filled with zeros (!). And there was no check for zeros in Net-SNMP! I have fixed Net-SNMP, and now there is no problem with PHP crashing. I will try to report about.
 [2014-10-04 12:27 UTC]
-Status: Feedback +Status: Not a bug
 [2014-10-04 12:27 UTC]
This is a really bad idea to wrap some external library calls with crash-preventing/recovering techniques.
PHP Copyright © 2001-2020 The PHP Group
All rights reserved.
Last updated: Mon Jul 06 22:01:03 2020 UTC