Bug #64467 [Opn->Csd]: Segmentation fault after imap_reopen failure
Edit report at https://bugs.php.net/bug.php?id=64467&edit=1
ID: 64467
Updated by: felipe@php.net
Reported by: askalski at gmail dot com
Summary: Segmentation fault after imap_reopen failure
-Status: Open
+Status: Closed
Type: Bug
Package: IMAP related
Operating System: Ubuntu 12.04 LTS
PHP Version: master-Git-2013-03-20 (Git)
Block user comment: N
Private report: N
New Comment:
Automatic comment on behalf of felipensp@gmail.com
Revision: http://git.php.net/?p=php-src.git;a=commit;h=60dcc5851f0dd7cf387270d6ba243f9ac46bc396
Log: - Fixed bug #64467 (Segmentation fault after imap_reopen failure) patch by: askalski at gmail
dot com
Previous Comments:
------------------------------------------------------------------------
[2013-03-20 16:30:08] askalski at gmail dot com
Description:
------------
Versions: 5.2, 5.3, 5.4, also confirmed on latest git master
(78acb84b6e8fc07974283ce30c24596444d18cf7)
PHP will crash with a Segmentation Fault after imap_reopen() fails with the error message
"imap_reopen(): Couldn't re-open stream ..."
When the UW-IMAP function 'mail_open' returns NIL after having been passed a valid
MAILSTREAM pointer, this means UW-IMAP closed and freed the MAILSTREAM. However, PHP ignores this
and returns FALSE without zeroing out imap_le_struct->imap_stream and calling zend_list_delete on
the resource.
Because the resource was not freed, mail_close_it (the resource destructor) gets called on an
invalid pointer during request shutdown. If you're lucky, this crashes PHP with a Segmentation
Fault. (If you're unlucky, you've got a corrupt PHP interpreter handling new requests...)
Test script:
---------------
<?php
/* This should succeed */
$imap = imap_open("INBOX", "", "");
echo "imap_open returned: ";
var_dump($imap);
/* This should fail */
$reopen = imap_reopen($imap, "{this*connection*will*fail}");
echo "imap_reopen returned: ";
var_dump($reopen);
flush();
/* Brace yourself for a segfault. UW-IMAP freed the MAILSTREAM structure,
* but PHP did not null out the pointer or free the resource. When the
* script exits, it will call the resource destructor (mail_close_it)
* on a pointer that was already freed.
*/
?>
Expected result:
----------------
No crash.
Actual result:
--------------
$ /tmp/z/bin/php -v
PHP 5.6.0-dev (cli) (built: Mar 20 2013 12:13:31)
Copyright (c) 1997-2013 The PHP Group
Zend Engine v2.6.0-dev, Copyright (c) 1998-2013 Zend Technologies
$ /tmp/z/bin/php imap-crash.php
imap_open returned: resource(4) of type (imap)
Warning: imap_reopen(): Couldn't re-open stream in /tmp/imap-crash.php on line 10
imap_reopen returned: bool(false)
Segmentation fault (core dumped)
------------------------------------------------------------------------
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Edit this bug report at https://bugs.php.net/bug.php?id=64467&edit=1
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