ID:               35594
 User updated by:  rabbitt at gmail dot com
 Reported By:      rabbitt at gmail dot com
 Status:           Closed
 Bug Type:         Reproducible crash
 Operating System: Linux 2.6.13
 PHP Version:      4.4.1
 New Comment:

While I appreciate the quickness with which you replied, as well as
applying the patch I provided, I should note that, after having
researched this bug a bit more, it might be a bit hasty to conclude
that my patch is a perfect fix. 

It seems that the static (struct _getopt_data) variable 'getopt_data'
is having it's member's (__nextchar) data overwritten in memory somehow
during the call to efree() in free_argv()
(ext/standard/basic_functions.php line 1430). While my patch enables
the resetting of getopt_data, it is probably best to not consider it a
safe transaction as, by that point, the memory address might have been
usurped already by something else. Although I haven't been able to
detect any problems with setting optind to zero (which causes
getopt_data to be reinitialized and __nextchar set to NULL), it might
be best to look into why the getopt_data.__nextchar is getting
overriden in the first place by someone with a more intimate
understanding of php internals.

Again, thanks for the speedy response and resolution - as well as all
the hard work you all have done making this such a great language!

--
Carl P. Corliss


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

[2005-12-08 04:26:22] [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.



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

[2005-12-08 04:01:16] rabbitt at gmail dot com

Additional note: I found this bug on 4.3.12, 4.4.1, and 5.0.5.

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

[2005-12-08 03:58:28] rabbitt at gmail dot com

The following patch appears to fix the problem:

--- ext/standard/basic_functions.c      2005-12-07 20:41:49.000000000
-0500
+++ ext/standard/basic_functions.c      2005-12-07 20:44:59.000000000
-0500
@@ -1597,6 +1597,9 @@
        /* Disable getopt()'s error messages. */
        opterr = 0;

+       /* Force reinitialization of getopt() (via optind reset) on
every call. */
+       optind = 0;
+
        /* Invoke getopt(3) on the argument array. */
 #ifdef HARTMUT_0
        while ((o = getopt_long(argc, argv, options, longopts,
&longindex)) != -1) {

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

[2005-12-08 03:56:16] rabbitt at gmail dot com

Description:
------------
Without long options built into zif_getopt(), zif_getopt()'s calls to
getopt() will only return a populated result once. The reason for this
is that 'optind' does not get reset on each call to getopt(). optind is
used to keep track of the most option processed internally in getopt().
Once getopt() has finished processing the options, optind remains at
the last value it was set to (typically, at this point, optind ==
argc). 

The problem with this is that when getopt() is called a second time, it
thinks that it's already finished with processing the options due to
optind being equal to argc. Worse still, with long optoins built in
(-DHARTMUT_0), it causes a segfault in glibc's getopt.c (function:
_getopt_internal_r() - line 521 specifically).



Reproduce code:
---------------
create file called test.php and add:

<?php
    print_r(@getopt('t', array('test')));
    print_r(@getopt('t', array('test')));
?>


then run: 
php test.php -t

Expected result:
----------------
Array
(
    [t] =>
)
Array
(
    [t] =>
)


Actual result:
--------------
One of two things will happen:

Array
(
    [t] =>
)
Array
(
)


or:

Array
(
)
Segmentation fault (core dumped)


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


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