Re: hard links create local DoS vulnerability and security problems

Amon Ott
2003-11-25T08:15:57Z

On Dienstag, 25. November 2003 01:35, Chris Wright wrote:
> * bill davidsen (davidsen@tmr.com) wrote:
> >
> > While I think you're overblowing the problem, it is an issue which might
> > be addressed in SE Linux or somewhere. I have an idea on that, but I
> > want to look before I suggest anything.
>
> SELinux controls hard link creation by checking, among other things,
> the security context of the process attempting the link, and the security
> context of the target (oldpath). Other MAC systems do similar, and some
> patches such as grsec and owl simply disable linking to files the user
> can't read/write to for example.

..and in RSBAC, LINK_HARD has been a controlled separate type of access since
the very first version back in 1997. It has always been treated like a write
access to the target file by all decision modules, because of the
implications mentioned in this thread.

Amon.
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