[Fwd: bug in odbc extension http://bugs.php.net/bug.php?id=37527]

php.internals

Alexandra S.

18 years ago
Hi, I am attaching here a patch for this bug. Please review it. -------- Original Message -------- Subject: bug in odbc extension http://bugs.php.net/bug.php?id=37527 Date: Tue, 18 Sep 2007 15:29:23 +0200 From: Alexandra S. <alexandra@zend.com> To: internals@lists.php.net Hi, I have been trying to work on this bug. The problem here is in this scenario: 1. odbc connection is established. 2. odbc connection is closed. 3. trying to do a request (example: odbc_exec) to the database using the closed connection -> crash. As far as I can understand from reading the odbc_exec() function, ZEND_FETCH_RESOURCE2 should return false,, so we do not advance to the SQLAllocStmt call that crashes. I checked with php 5.2.4 on both Linux and Windows and ZEND_FETCH_RESOURCE2 does not return false. The reason for it is in the odbc_close function - for(i = 1; i < nument; i++){ ptr = zend_list_find(i, &type); if(ptr && (type == le_result)){ res = (odbc_result *)ptr; if(res->conn_ptr == conn){ zend_list_delete(i); } } } Here only the previous statements of this connection are deleted and not the connection itself. In the odbc_close_all function all the statements are deleted, and then all the connections. I suggest to add the deletion of the connection itself to the odbc_close function - so the ZEND_FETCH_RESOURCE2 check will actually work. The situation now is that check do not work and we try all the time to call SQL actions with no existent connections. Example for possible solution: for(i = 1; i < nument; i++){ ptr = zend_list_find(i, &type); if(ptr && (type == le_result)){ res = (odbc_result *)ptr; if(res->conn_ptr == conn){ zend_list_delete(i); } } if(ptr && (type == (is_pconn?le_pconn:le_conn))){ res = (odbc_result *)ptr; if(res == conn){ zend_list_delete(i); } } } Alexandra Shpindovsky

Dmitry Stogov

18 years ago
Hi Alexandra, I'm not sure in tis patch. It does the same as double calling to zend_list_delete(Z_LVAL_PP(pv_conn)); Also your fix may cause deletion of connection (le_conn) before deletion of related results (le_result). Is it allowed? Thanks. Dmitry.