Mário Gamito wrote:

Hi,

This is a bit of-topic, but since it has to do with /tmp permissions here it goes. Anyway, I'm sorry in advance for posting this.

I have this PHP script (simplificated here), called delete_tmp.php that basically calls external commands:

<?php $session_file = '/tmp/sess_89765' system(''rm -f' . ' ' . $session_file); ?>

delete_tmp.php file is owned by gamito.users

/tmp/sess_89765 file has permissions -rw------ and is owned by gamito.users

My /tmp permissions are rwxrwxrwt and is owned by root.root

I know that the the sticky bit only allows files to be deleted by their owners, the owner of the directory or by root.

Never the less, i can switch to /tmp directory and delete sess_89765 file as user gamito.

If I run: $ php delete_tmp.php

as root, it deletes sess_89765 file.

But if I do the same has user gamito, it doesn't delete the file !!!

Ideas ?

PHP, being run from the web interface, is run as whatever ID Apache is run as. Apache is not user gamito. On a file with -rw------ permission users in the group will not be allowed to delete the file.