Edit report at http://bugs.php.net/bug.php?id=51329&edit=1
ID: 51329
Comment by: gergely dot fabian at radix-technologies dot com
Reported by: gergely dot fabian at radix-technologies dot com
Summary: call_user_func_array() crashes with autoload in
recursive calls
Status: Bogus
Type: Bug
Package: Reproducible crash
Operating System: Ubuntu
PHP Version: 5.2.13
New Comment:
This is not infinite recursion (is 31/25 recursion too deep?).
See my comment with putting one element to call stack "fixing" later
autoloading (2010-03-19 09:38 UTC).
This is an autoloading/call_user_func_array bug imho. Otherwise if it
would be normal for this to happen, why does class_exists() call right
before the segfaulting place fix it?
Previous Comments:
------------------------------------------------------------------------
[2010-03-21 19:24:32] [email protected]
Infinite recursion is known to segfault and expected behavior. See other
reports about it.
------------------------------------------------------------------------
[2010-03-19 11:38:45] gergely dot fabian at radix-technologies dot com
I managed to reproduce this bug (I guess it's the same) in another way,
which is a lot closer to our original test case (that was about having a
given number of calls in the call stack causing later autoload of
call_user_func_array() to fail, but if we had more number of calls in
call stack, then there was no segfault).
This code will have a segfault in the 25th call (it mainly depends on
the number of parameters given to "callback"). If we miss calling
call_user_func_array() in the 25th recursion (and simply make another
recursion) then later call_user_func_array() calls will be ok. I guess
making a simple recursion at 25th steps mask (or fixes) the bug in the
call stack.
<?php
$limit = 25; // till when to autoload classes
// change $limit2 to 25, and P25's autoload will be missed (and an
additional callback will be called before next autoloading)
// then there is no segmentation fault, and it runs till 50
$limit2 = 24; // re-enable autoloading after this limit
$limit3 = 50; // iterate till this
for($i = 1; $i <= $limit3; $i++){
$f = "<?php
echo \"P$i loaded\\n\";
class P$i{
public static function execute_me(){
return \"P$i executed\\n\";
}
}";
file_put_contents("P$i.class.php", $f);
}
function __autoload($class_name) {
require_once $class_name . '.class.php';
}
function callback($limit, $limit2, $i = 1){
global $limit3;
echo "Calling callback $i\n";
if ($i < $limit || $i > $limit2) // enable some $i where we won't
autoload
{
//class_exists("P$i");
echo call_user_func_array(array("P$i", 'execute_me'), array());
}
if ($i < $limit3) callback($limit, $limit2, $i+1);
}
callback($limit, $limit2);
------------------------------------------------------------------------
[2010-03-19 10:29:56] gergely dot fabian at radix-technologies dot com
Description:
------------
PHP 5.2.13 (cli) (built: Mar 19 2010 09:37:12) (configured with
./configure --prefix=$HOME --enable-debug)
2.6.31-20-generic #58-Ubuntu SMP Fri Mar 12 04:38:19 UTC 2010 x86_64
GNU/Linux
Calling class methods with call_user_func_array() in a recursive
call-chain - if call_user_func_array() autoloads the subsequent class on
each step - will cause a Segmentation fault (if the recursion is enough
deep).
If I run the sample script then I'll get a Segmentation fault at 31st
call.
This was reproducible both on PHP 5.2.13 and 5.2.10-2ubuntu6.4.
There is no segfault though if call_user_func_array() is preceded by a
call to class_exists().
Test script:
---------------
$limit = 50;
for($i = 1; $i <= $limit; $i++){
$f = "<?php
echo \"P$i loaded\\n\";
class P$i{
public static function execute_me(){
return \"P$i executed\\n\";
}
}";
file_put_contents("P$i.class.php", $f);
}
function __autoload($class_name) {
require_once $class_name . '.class.php';
}
function callback($limit, $i = 1){
//class_exists("P$i");
echo call_user_func_array(array("P$i", 'execute_me'), array());
if($i < $limit) callback($limit, $i+1);
}
callback($limit);
Expected result:
----------------
P1 loaded
P1 executed
P2 loaded
P2 executed
P3 loaded
P3 executed
...
...
P50 loaded
P50 executed
Actual result:
--------------
P1 loaded
P1 executed
P2 loaded
P2 executed
P3 loaded
P3 executed
...
...
P30 loaded
P30 executed
P31 loaded
Segmentation fault (writing memory)
This is the gdb backtrace:
Core was generated by `php call_user_func_array_bug.php'.
Program terminated with signal 11, Segmentation fault.
#0 0x0000000000586ee9 in zif_call_user_func_array (ht=<value optimized
out>, return_value=0x1d5adf8, return_value_ptr=<value optimized out>,
this_ptr=<value optimized out>, return_value_used=<value optimized
out>) at /home/user/opt/php-5.2.13/ext/standard/basic_functions.c:5201
5201 func_params_ht = Z_ARRVAL_PP(params);
(gdb) bt
#0 0x0000000000586ee9 in zif_call_user_func_array (ht=<value optimized
out>, return_value=0x1d5adf8, return_value_ptr=<value optimized out>,
this_ptr=<value optimized out>, return_value_used=<value optimized
out>) at /home/user/opt/php-5.2.13/ext/standard/basic_functions.c:5201
#1 0x00000000006526b0 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2611b0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:200
#2 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#3 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e261490) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#4 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#5 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e261770) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#6 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#7 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e261a50) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#8 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#9 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e261d30) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#10 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#11 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e262010) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#12 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#13 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2622f0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#14 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#15 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2625d0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#16 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#17 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2628b0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#18 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#19 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e262b90) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#20 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#21 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e262e70) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#22 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#23 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e263150) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#24 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#25 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e263430) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#26 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#27 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e263710) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#28 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#29 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2639f0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#30 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#31 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e263cd0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#32 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#33 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e263fb0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#34 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#35 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e264290) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#36 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#37 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e264570) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#38 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#39 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e264850) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#40 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#41 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e264b30) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#42 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#43 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e264e10) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#44 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#45 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2650f0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#46 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#47 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2653d0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#48 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#49 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2656b0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#50 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#51 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e265990) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#52 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#53 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e265c70) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#54 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#55 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e265f50) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#56 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#57 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e266230) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#58 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#59 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e266510) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#60 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#61 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e2667f0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#62 0x000000000064df04 in execute (op_array=0x1d414a0) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#63 0x0000000000652056 in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fff1e266b30) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:234
#64 0x000000000064df04 in execute (op_array=0x1d12c20) at
/home/user/opt/php-5.2.13/Zend/zend_vm_execute.h:92
#65 0x000000000062b96a in zend_execute_scripts (type=<value optimized
out>, retval=0x0, file_count=3) at
/home/user/opt/php-5.2.13/Zend/zend.c:1134
#66 0x00000000005ea9d3 in php_execute_script (primary_file=<value
optimized out>) at /home/user/opt/php-5.2.13/main/main.c:2036
#67 0x000000000069a1e7 in main (argc=<value optimized out>, argv=<value
optimized out>) at /home/user/opt/php-5.2.13/sapi/cli/php_cli.c:1165
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/bug.php?id=51329&edit=1
