From: John Wood <john.wood@gmx.com>
To: Andi Kleen <ak@linux.intel.com>
Cc: "John Wood" <john.wood@gmx.com>,
"Valdis Klētnieks" <valdis.kletnieks@vt.edu>,
kernelnewbies@kernelnewbies.org,
"Kees Cook" <keescook@chromium.org>,
kernel-hardening@lists.openwall.com
Subject: Re: Notify special task kill using wait* functions
Date: Fri, 9 Apr 2021 18:08:14 +0200 [thread overview]
Message-ID: <20210409160814.GA4937@ubuntu> (raw)
In-Reply-To: <20210409150621.GJ3762101@tassilo.jf.intel.com>
Hi,
On Fri, Apr 09, 2021 at 08:06:21AM -0700, Andi Kleen wrote:
> > > Any caching of state is inherently insecure because any caches of limited
> > > size can be always thrashed by a purposeful attacker. I suppose the
> > > only thing that would work is to actually write something to the
> > > executable itself on disk, but of course that doesn't always work either.
> >
> > I'm also working on this. In the next version I will try to find a way to
> > prevent brute force attacks through the execve system call with more than
> > one level of forking.
>
> Thanks.
>
> Thinking more about it what I wrote above wasn't quite right. The cache
> would only need to be as big as the number of attackable services/suid
> binaries. Presumably on many production systems that's rather small,
> so a cache (which wouldn't actually be a cache, but a complete database)
> might actually work.
Thanks. I will keep it in mind.
>
> -Andi
Regards,
John Wood
next prev parent reply other threads:[~2021-04-09 16:08 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210330173459.GA3163@ubuntu>
[not found] ` <79804.1617129638@turing-police>
[not found] ` <20210402124932.GA3012@ubuntu>
[not found] ` <106842.1617421818@turing-police>
[not found] ` <20210403070226.GA3002@ubuntu>
[not found] ` <145687.1617485641@turing-police>
[not found] ` <20210404094837.GA3263@ubuntu>
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[not found] ` <20210405073147.GA3053@ubuntu>
[not found] ` <115437.1617753336@turing-police>
2021-04-07 17:51 ` Notify special task kill using wait* functions John Wood
2021-04-07 20:38 ` Valdis Klētnieks
2021-04-08 1:51 ` Andi Kleen
2021-04-09 14:29 ` John Wood
2021-04-09 15:06 ` Andi Kleen
2021-04-09 16:08 ` John Wood [this message]
2021-04-09 23:28 ` Valdis Klētnieks
2021-04-11 8:46 ` John Wood
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