ID:               38648
 Updated by:       [EMAIL PROTECTED]
 Reported By:      songmaqd at hotmail dot com
-Status:           Closed
+Status:           Bogus
 Bug Type:         Streams related
 Operating System: UNIX
 PHP Version:      5CVS-2006-08-30 (CVS)
 Assigned To:      pollita
 New Comment:

Changing status for record keeping purposes.

Not actually bogus, but it is a duplicate of Bug#36515 which wins
because it was reported first.

For the record though, your report and analysis was much better :)


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

[2006-10-11 23:12:01] [EMAIL PROTECTED]

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.

Fix will appear in 5.2.0RC6

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

[2006-09-01 12:57:19] [EMAIL PROTECTED]

Assigned to the maintainer.

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

[2006-08-31 10:07:31] songmaqd at hotmail dot com

Here is the reproduce script:
<?php
class strtoupper_filter extends php_user_filter {
  function filter($in, $out, &$consumed, $closing)
    {
      while ($bucket = stream_bucket_make_writeable($in)) {}
    }
}
stream_filter_register("strtoupper", "strtoupper_filter");
$fp = fopen("foo-bar.txt", "w");
stream_filter_append($fp, "strtoupper");
fwrite($fp, "Line1\n");

Note:
1. This bug can not be reproduced on Linux platform. My distro is SuSE
10.1. I can reproduce the bug on one certain UNIX platform.

2.The above script is for testing purpose and is deliberated written
like that. It is not following the stream filter coding way.

3. Here is some debugger info. "php_stream_bucket_unlink" was called
twice I guess the second call is to clean the system resource and
"brigade" is "0x0" at this moment.
**** ****
[1] stopped in php_stream_bucket_unlink at line 235 in file "filter.c" 
($t2)
  235           if (bucket->prev) {
(/tmp/dbx) print *bucket
(next = 0x0, prev = 0x0, brigade = 0x220C70E8, buf = "Line1.", buflen =
6, own_buf = 0, is_persistent = 0, refcount = 1)
(/tmp/dbx) print *bucket->brigade
(head = 0x2223D000, tail = 0x2223D000)
(/tmp/dbx) print *bucket->brigade->head
(next = 0x0, prev = 0x0, brigade = 0x220C70E8, buf = "Line1.", buflen =
6, own_buf = 0, is_persistent = 0, refcount = 1)
(/tmp/dbx) next
stopped in php_stream_bucket_unlink.$b156 at line 238 in file
"filter.c"  ($t2)
  238                   bucket->brigade->head = bucket->next;
(/tmp/dbx) list
  239           }
  240           if (bucket->next) {
  241                   bucket->next->prev = bucket->prev;
  242           } else if (bucket->brigade) {
  243                   bucket->brigade->tail = bucket->prev;
  244           }
  245           bucket->brigade = NULL;
  246           bucket->next = bucket->prev = NULL;
  247   }
(/tmp/dbx) cont
[1] stopped in php_stream_bucket_unlink at line 235 in file "filter.c" 
($t2)
  235           if (bucket->prev) {
(/tmp/dbx) print *bucket
(next = 0x0, prev = 0x0, brigade = 0x0, buf = "", buflen = 0, own_buf =
0, is_persistent = 0, refcount = 0)
(/tmp/dbx) next
stopped in php_stream_bucket_unlink at line 240 in file "filter.c" 
($t2)
  240           if (bucket->next) {
(/tmp/dbx) next
stopped in php_stream_bucket_unlink at line 245 in file "filter.c" 
($t2)
  245           bucket->brigade = NULL;
(/tmp/dbx) next
stopped in php_stream_bucket_unlink at line 246 in file "filter.c" 
($t2)
  246           bucket->next = bucket->prev = NULL;
(/tmp/dbx) next
stopped in php_stream_bucket_unlink at line 247 in file "filter.c" 
($t2)
  247   }
(/tmp/dbx) cont
program exited
**** ****

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

[2006-08-30 08:48:23] [EMAIL PROTECTED]

Thank you for this bug report. To properly diagnose the problem, we
need a short but complete example script to be able to reproduce
this bug ourselves. 

A proper reproducing script starts with <?php and ends with ?>,
is max. 10-20 lines long and does not require any external 
resources such as databases, etc. If the script requires a 
database to demonstrate the issue, please make sure it creates 
all necessary tables, stored procedures etc.

Please avoid embedding huge scripts into the report.



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

[2006-08-30 05:49:47] songmaqd at hotmail dot com

Description:
------------
In source file "main/streams/filter.c", function "PHPAPI void
php_stream_bucket_unlink(php_stream_bucket *bucket TSRMLS_DC)
" needs some additional sanity check for NULL pointer of "brigade".
Otherwise it leads to core dump if "brigade" is NULL.

A possible example for this fix is:
PHPAPI void php_stream_bucket_unlink(php_stream_bucket *bucket
TSRMLS_DC)
{
        if (bucket->prev) {
                bucket->prev->next = bucket->next;
        } else if (bucket->brigade) /*newly added*/{
                bucket->brigade->head = bucket->next;
        }
        if (bucket->next) {
                bucket->next->prev = bucket->prev;
        } else if (bucket->brigade) /*newly added*/{
                bucket->brigade->tail = bucket->prev;
        }
        bucket->brigade = NULL;
        bucket->next = bucket->prev = NULL;
}




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


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