Re: [PATCH] BSD Secure Levels: claim block dev in file struct rather than inode struct, 2.6.11-rc2-mm1 (3/8)

David Wagner
2005-02-08T14:35:27Z

>The attack is to hardlink some tempfile name to some file you want
>over-written. This usually involves just a little bit of work, such as
>recognizing that a given root cronjob uses an unsafe predictable filename
>in /tmp (look at the Bugtraq or Full-Disclosure archives, there's plenty).
>Then you set a little program that sleep()s till a few seconds before
>the cronjob runs, does a getpid(), and then sprays hardlinks into the
>next 15 or 20 things that mktemp() will generate...

Got it. Very good -- now I see. Thanks for the explanation.