Re: hard links create local DoS vulnerability and security problems

[John Bradford]

Quote from mru@xxxxxx (=?iso-8859-1?q?M=E5ns_Rullg=E5rd?=):
> John Bradford <john@xxxxxxxxxxxx> writes:
> 
> >> > They can truncate the file to zero length, though, then delete the
> >> > 'original' link, making all of the other links point to the zero
> >> > length file.
> >>=20
> >> It could be tricky to find those extra links if the original has bee=
> n
> >> deleted, of course.
> >
> > True, but as long as at least one of the links which has been made to
> > the original file is in a directory you have access to, you can simpl=
> y
> > create a new link to the file, truncate it, then delete your newly
> > created link, so actually deleting the 'original' link is not
> > necessarily a problem :-).
> 
> There's no need to make a new link, since any links will be owned by
> the original owner.  That was the concern in the first place.  The
> problem is finding a link after the file has been deleted.  It could
> be hidden away somewhere in a directory you don't have read or execute
> permission for.

Ah, OK, I was thinking of something else entirely :-)

John.
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