ID:               29012
 Updated by:       [EMAIL PROTECTED]
 Reported By:      cjbj at hotmail dot com
-Status:           Open
+Status:           Closed
 Bug Type:         OCI8 related
 Operating System: n/a
 PHP Version:      5.0.0RC3
 New Comment:

This bug has been fixed in CVS.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
 
Thank you for the report, and for helping us make PHP better.




Previous Comments:
------------------------------------------------------------------------

[2004-07-05 07:52:40] cjbj at hotmail dot com

Description:
------------
The mutex locking in _oci_open_session() in
php-5.0.0RC3/ext/oci8/oci.c at about line 2676 may allow a
possible race.  This was discovered from code inspection so I could be
wrong.

The current code is:

   if (zend_ts_hash_find(persistent_sessions, hashed_details.c,
hashed_details.len+1, (void **) &session_list) != SUCCESS) {
       zend_llist tmp;
       /* first session, set up a session list */
       zend_llist_init(&tmp, sizeof(oci_session), (llist_dtor_func_t)
_session_pcleanup, 1);
       zend_ts_hash_update(persistent_sessions, hashed_details.c,
hashed_details.len+1, &tmp, sizeof(zend_llist), (void **)
&session_list);
   } else {
       mutex_lock(mx_lock);

       /* session list found, search for an idle session or an already
opened session by the current thread */
       session = zend_llist_get_first(session_list);
       while ((session != NULL) && session->thread && (session->thread
!= thread_id())) {
           session = zend_llist_get_next(session_list);
       }

       if (session != NULL) {
           /* mark session as busy */
           session->thread = thread_id();
       }
       mutex_unlock(mx_lock);
   }


I don't understand why there is no locking around the
zend_llist_init() or even zend_ts_hash_find() calls.  If multiple
users log in at once then does zend_ts_hash_find() guarentee to return
SUCCESS for only one thread?  If not, a suggested change is:

   mutex_lock(mx_lock);
   if (zend_ts_hash_find(persistent_sessions, hashed_details.c,
hashed_details.len+1, (void **) &session_list) != SUCCESS) {
       zend_llist tmp;
       /* first session, set up a session list */
       zend_llist_init(&tmp, sizeof(oci_session), (llist_dtor_func_t)
_session_pcleanup, 1);
       zend_ts_hash_update(persistent_sessions, hashed_details.c,
hashed_details.len+1, &tmp, sizeof(zend_llist), (void **)
&session_list);
   } else {

       /* session list found, search for an idle session or an already
opened session by the current thread */
       session = zend_llist_get_first(session_list);
       while ((session != NULL) && session->thread && (session->thread
!= thread_id())) {
           session = zend_llist_get_next(session_list);
       }

       if (session != NULL) {
           /* mark session as busy */
           session->thread = thread_id();
       }
   }
   mutex_unlock(mx_lock);




------------------------------------------------------------------------


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