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:
> 
> >> Right... but non-privileged users _can't_ delete these extra links, =
> even=20
> >> if they notice them from the link count.
> >
> > 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.
> 
> It could be tricky to find those extra links if the original has been
> 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 simply
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 :-).

John.
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