ID: 37204
User updated by: mailslot at mac dot com
Reported By: mailslot at mac dot com
Status: Open
Bug Type: Reproducible crash
Operating System: Linux 2.4.21-9.EL
PHP Version: 5.1.2
New Comment:
Okay... no recursion limits. Fine. I'd rather have to enable
dangerous recursion levels, but I can live without it.
I still think this bug is valid. Could you please respect the
configuration defines that set limits for script execution
time and memory usage? These values are completely ignored
during recursion bombs. Surely that's not expected behavior.
If they worked as advertised, this bug would never have even
manifested itself.
Previous Comments:
------------------------------------------------------------------------
[2006-04-26 03:13:56] judas dot iscariote at gmail dot com
the recursion Limit problem is well known (for years), and there is no
solution at this time.( because solution should be adecuate for any
legitimate use, not just for average use)
Use Xdebug to set a recursion limit in your dev enviroment.
------------------------------------------------------------------------
[2006-04-26 00:45:04] mailslot at mac dot com
Description:
------------
I encountered this problem while debugging an exception logging class.
Infinite recursion problems are a coding mistake, but I've never seen
one take down Apache before. Apache will grow in size until virtual
memory starts swapping. The CPU will be at 100% and eventually, appears
to halt. Limits, obviously, are not being used... yet.
Reproduce code:
---------------
<?php
class Eggception extends Exception
{
public function __construct($ex)
{
parent::__construct($ex);
try {
// let's say that a database object
throws derived Eggception
throw new EggceptionSubclass('It
happens');
// this is valid (not infinitely
recursive)
//throw new Exception('It happens');
} catch (Exception $e) {
// should swallow exception, right?
// not before a never-ending recursive
bomb
}
}
}
class EggceptionSubclass extends Eggception {}
// the following causes a runaway process (memory leak &
// CPU spike) with Apache 2.0.55 and PHP 5.1.2
// rather quickly, all server resources become exhausted
// without proper process limits, potentially crashing the
// entire machine.
throw new Eggception('Exception Bomb');
?>
Expected result:
----------------
A timeout after a large CPU spike... perhaps a stack overflow error.
An exception recursion counter that kills a script whenever it's 1,000
layers deep in an exception stack... that would be great.
Actual result:
--------------
The process (PHP or Apache, depending on which are used to execute the
script) will consume as much memory allowed while pegging the CPU at
100% utilization. Kill -9 works fine.
Workarounds include ulimit and softlimit.
------------------------------------------------------------------------
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Edit this bug report at http://bugs.php.net/?id=37204&edit=1
