Red Hat Bugzilla – Bug 121454
umask change via umask() function call persists after script is completed
Last modified: 2009-09-09 20:22:48 EDT
From Bugzilla Helper: User-Agent: Mozilla/5.0 Galeon/1.2.8 (X11; Linux i686; U;) Gecko/20030212 Description of problem: When I call umask(0002) from a php script the umask stays set for all subsequent calls to the server that hit that httpd process. Version-Release number of selected component (if applicable): php-4.3.4-1.1 How reproducible: Always Steps to Reproduce: 1.install umask.php in a directory accessible by the web server ####### umask.php <?php if ( isset( $_GET['newmask']) ) { print "newmask is set to $_GET[newmask] calling umask()<br>\n"; print umask($_GET['newmask']) ."<br>\n"; } else { print "umask is ". umask() . "<br>\n"; } ?> ################# end of umask.php 2. copy chkmask.sh somwhere on the server 3. run chkumask.sh [hostnameofserver] this will start looping and making calls to the umask.php script on the server defaults to value of $HOSTNAME 4. with a broser or whatever go to http://servername/locationofumask.php?newmask=0002 5 observe output of chkumask.sh depending on the number of threads started by httpd the umask changes from 18(octal 22, the default) to 2 for that thread. refresh the browser several times to have more threads get changed. Actual Results: output of chkumask.sh: using 10.23.0.137 as wget host 04/21/04 host: 10.23.0.137 umask is 2<br> 04/21/04 host: 10.23.0.137 umask is 18<br> 04/21/04 host: 10.23.0.137 umask is 2<br> 04/21/04 host: 10.23.0.137 umask is 2<br> 04/21/04 host: 10.23.0.137 umask is 18<br> 04/21/04 host: 10.23.0.137 umask is 18<br> 04/21/04 host: 10.23.0.137 umask is 18<br> 04/21/04 host: 10.23.0.137 umask is 2<br> 04/21/04 host: 10.23.0.137 umask is 2<br> 04/21/04 host: 10.23.0.137 umask is 18<br> 04/21/04 host: 10.23.0.137 umask is 2<br> Expected Results: that the umask remain 18 for all threads as it is after serverice httpd restart Additional info: reducing the number of threads started by httpd to one will make this redily apparent: I started httpd with this: <IfModule prefork.c> StartServers 1 MinSpareServers 1 MaxSpareServers 1 MaxClients 1 MaxRequestsPerChild 1000 </IfModule> #<IfModule prefork.c> #StartServers 8 #MinSpareServers 5 #MaxSpareServers 20 #MaxClients 150 #MaxRequestsPerChild 1000 #</IfModule> restarted and indeed only had one child processas expected. [root@compaq2 conf]# ps axf|grep [h]ttpd 12144 ? S 0:01 /usr/sbin/httpd 12147 ? S 0:01 \_ /usr/sbin/httpd I got all 18s and then ran the script that does the umask and this is what happened: Wed Apr 21 10:29:47 CDT 2004 umask is 18<br> Wed Apr 21 10:29:48 CDT 2004 umask is 18<br> Wed Apr 21 10:29:49 CDT 2004 umask is 18<br> Wed Apr 21 10:29:50 CDT 2004 umask is 18<br> Wed Apr 21 10:29:51 CDT 2004 umask is 18<br> Wed Apr 21 10:29:52 CDT 2004 umask is 18<br> Wed Apr 21 10:29:53 CDT 2004 umask is 18<br> Wed Apr 21 10:29:54 CDT 2004 umask is 18<br> Wed Apr 21 10:29:55 CDT 2004 umask is 18<br> Wed Apr 21 10:29:56 CDT 2004 umask is 18<br> Wed Apr 21 10:29:57 CDT 2004 umask is 18<br> Wed Apr 21 10:29:58 CDT 2004 umask is 18<br> Wed Apr 21 10:29:59 CDT 2004 umask is 18<br> Wed Apr 21 10:30:01 CDT 2004 umask is 18<br> Wed Apr 21 10:30:02 CDT 2004 umask is 18<br> Wed Apr 21 10:30:03 CDT 2004 umask is 18<br> #instant change Wed Apr 21 10:30:04 CDT 2004 umask is 2<br> Wed Apr 21 10:30:05 CDT 2004 umask is 2<br> Wed Apr 21 10:30:06 CDT 2004 umask is 2<br> Wed Apr 21 10:30:07 CDT 2004 umask is 2<br> Wed Apr 21 10:30:08 CDT 2004 umask is 2<br> Wed Apr 21 10:30:09 CDT 2004 umask is 2<br> Wed Apr 21 10:30:10 CDT 2004 umask is 2<br> Wed Apr 21 10:30:12 CDT 2004 umask is 2<br> Wed Apr 21 10:30:13 CDT 2004 umask is 2<br> Wed Apr 21 10:30:14 CDT 2004 umask is 2<br> Wed Apr 21 10:30:15 CDT 2004 umask is 2<br> Wed Apr 21 10:30:16 CDT 2004 umask is 2<br> Wed Apr 21 10:30:17 CDT 2004 umask is 2<br> Wed Apr 21 10:30:18 CDT 2004 umask is 2<br> Wed Apr 21 10:30:19 CDT 2004 umask is 2<br>
You're using PHP as an in-process scripting language: if a script changes one of the properties of the httpd child process, such as the umask, then those properties are not reset after the script terminates. That is the nature of in-process scripting languages. If you want to use PHP as an out-of-process scripting language, you can do so by replacing the AddType in /etc/httpd/conf.d/php.conf with: Action php-script /cgi-bin/php AddHandler php-script .php and running, as root: # ln /usr/bin/php /var/www/cgi-bin/php
OK, Thanks. If this is NOTABUG, what has changed since rhl 7.3? this behavior is not evident in php-4.1.2-7.3.6 and the php docs on umask() say: I see this behavior on a rh9 box too but not with RH built rpms. umask() sets PHP's umask to mask & 0777 and returns the old umask. When PHP is being used as a server module, the umask is restored when each request is finished. This is clearly not happening. I can't believe that his behavior is not a bug since you are shipping a product that allows a script to change the default expected environment fo scripts that follow. ESPECIALLY in the possible sensitive area of file permissions.
Ah, my apologies, I didn't realise this was a regression.
I should have mentioned it. I am going to ask the php general list about it as well.
hmm I notice that my chkumask script did not make it to tbe post. Since I think it realy does make tracking this thing down easier here it is. ########## chkumask.sh #!/bin/sh if [ -n "$1" ] ; then echo "setting hostname to input host $1" myhost=$1 else myhost=$HOSTNAME fi echo "using $myhost as wget host" while [ 1 ]; do echo -n `date +'%D'` " host: $myhost " wget -q -O - "http://$myhost/umask.php" sleep 1 done ############ end of of chkumask.sh
It's a bug in the Apache 2.0 support in PHP: I've got a patch which I'll integrate and submit upstream.
Fix integrated for the php-4.3.6-1.1 update.
Fix included in FEDORA-2004-118 update, thanks for the report. http://www.redhat.com/archives/fedora-announce-list/2004-May/msg00025.html