From: thomas dot jarosch at intra2net dot com
Operating system: linux
PHP version: 5.2.6
PHP Bug Type: Reproducible crash
Bug description: IMAP crash if server shuts down
Description:
------------
Hello together,
if you use a webmail applications like Horde's IMP and restart the
server while an IMAP command is processing, PHP segfaults on request
shutdown.
Here's a backtrace of the crash:
(gdb) bt
#0 0x632f6564 in ?? ()
#1 0x01a6b575 in mail_close_full (stream=0x87b8ad8, options=0) at
mail.c:1361
#2 0x01a494e3 in mail_close_it (rsrc=0xb7977840)
at /usr/src/redhat/BUILD/php-5.2.6/ext/imap/php_imap.c:229
#3 0x006dacc7 in list_entry_destructor (ptr=0xb7977840)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_list.c:184
#4 0x006d8a3a in zend_hash_del_key_or_index (ht=0x7cb480, arKey=0x0,
nKeyLength=0, h=81, flag=1)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_hash.c:497
#5 0x006da915 in _zend_list_delete (id=81)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_list.c:58
#6 0x006cb9ed in _zval_dtor_func (zvalue=0xb79d7a74)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_variables.c:60
#7 0x006be95e in _zval_dtor (zvalue=0xb79d7a74)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_variables.h:35
#8 0x006bebac in _zval_ptr_dtor (zval_ptr=0xb79a9610)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_execute_API.c:414
#9 0x006d8b33 in zend_hash_destroy (ht=0xb7a1a71c)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_hash.c:526
#10 0x006eae64 in zend_object_std_dtor (object=0xb7b9bf08)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_objects.c:45
#11 0x006eb287 in zend_objects_free_object_storage
(object=0xb7b9bf08)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_objects.c:122
#12 0x006eec3f in zend_objects_store_free_object_storage
(objects=0x7cb528)
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_objects_API.c:89
#13 0x006be7c7 in shutdown_executor ()
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend_execute_API.c:299
#14 0x006cd48d in zend_deactivate ()
at /usr/src/redhat/BUILD/php-5.2.6/Zend/zend.c:860
#15 0x0067d8d2 in php_request_shutdown (dummy=0x0)
at /usr/src/redhat/BUILD/php-5.2.6/main/main.c:1486
#16 0x00742f2f in php_apache_request_dtor (r=0x8776f70)
at /usr/src/redhat/BUILD/php-5.2.6/sapi/apache2handler/sapi_apache2.c:469
#17 0x007438ce in php_handler (r=0x8776f70)
at /usr/src/redhat/BUILD/php-5.2.6/sapi/apache2handler/sapi_apache2.c:641
#18 0x08065f19 in ap_run_handler ()
#19 0x08068f61 in ap_invoke_handler ()
#20 0x080639d8 in ap_process_request ()
#21 0x0805e6b8 in _start ()
I took a look at the structures in #1 mail_close_full
(stream=0x87b8ad8, options=0), the memory was totally bogus and
already reused. To me this looks like a use-after-free issue.
While debugging I've found another crash in c-client's IMAP extension
and I will submit a patch upstream.
I was unable to find the source of this crash, but I suspect the
connection already gets closed and then PHP tries to close it twice
or something like that.
Reproduce code:
---------------
Move mails via IMAP to another folder and restart your IMAP server.
Expected result:
----------------
Error message "Connection to server died".
Actual result:
--------------
Segfault.
--
Edit bug report at http://bugs.php.net/?id=45188&edit=1
--
Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=45188&r=trysnapshot52
Try a CVS snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=45188&r=trysnapshot53
Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=45188&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=45188&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=45188&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=45188&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=45188&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=45188&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=45188&r=support
Expected behavior: http://bugs.php.net/fix.php?id=45188&r=notwrong
Not enough info: http://bugs.php.net/fix.php?id=45188&r=notenoughinfo
Submitted twice: http://bugs.php.net/fix.php?id=45188&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=45188&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=45188&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=45188&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=45188&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=45188&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=45188&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=45188&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=45188&r=mysqlcfg