From: "PaX Team" <pageexec@freemail.hu>
To: Nick Bowler <nbowler@elliptictech.com>,
Vasiliy Kulikov <segoon@openwall.com>
Cc: Kees Cook <keescook@chromium.org>,
Greg KH <gregkh@linuxfoundation.org>,
David Windsor <dwindsor@gmail.com>,
Roland Dreier <roland@purestorage.com>,
Djalal Harouni <tixxdz@opendz.org>,
kernel-hardening@lists.openwall.com,
Ubuntu security discussion <ubuntu-hardened@lists.ubuntu.com>,
linux-kernel@vger.kernel.org, spender@grsecurity.net
Subject: Re: [kernel-hardening] Re: Add overflow protection to kref
Date: Fri, 24 Feb 2012 23:59:47 +0200 [thread overview]
Message-ID: <4F481663.5371.216F475B@pageexec.freemail.hu> (raw)
In-Reply-To: <20120224191300.GA12553@albatros>
On 24 Feb 2012 at 23:13, Vasiliy Kulikov wrote:
> > But in this case, the principle does not apply because we can recover.
> > The reason we cannot recover from the stack protector case is because
> > the stack protector is reacting after the fact, which is not the case
> > here. Simply peg the reference count at the maximum value, neither
> > incrementing it nor decrementing it further.
>
> ...and simply loose one reference, which leads to use-after-free.
saturating the refcount keeps the protected object allocated, so it is
a memory leak, but it is not a use-after-free.
next prev parent reply other threads:[~2012-02-24 21:59 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-16 14:02 [kernel-hardening] Add overflow protection to kref David Windsor
2012-02-16 20:45 ` [kernel-hardening] " Kees Cook
2012-02-17 0:24 ` Greg Kroah-Hartman
2012-02-17 1:06 ` Kees Cook
2012-02-17 1:40 ` Greg KH
2012-02-17 2:11 ` [kernel-hardening] Re: [ubuntu-hardened] " Kees Cook
2012-02-17 2:48 ` David Windsor
2012-02-17 3:32 ` Greg KH
2012-02-17 6:33 ` Alexey Dobriyan
2012-02-17 13:23 ` [kernel-hardening] " pageexec
2012-02-17 7:59 ` Vasiliy Kulikov
2012-02-17 17:53 ` Greg KH
2012-02-17 17:54 ` Greg KH
2012-02-17 19:37 ` Vasiliy Kulikov
2012-02-17 23:39 ` Djalal Harouni
2012-02-18 1:44 ` Roland Dreier
2012-02-18 16:15 ` David Windsor
2012-02-18 16:35 ` Vasiliy Kulikov
2012-02-18 16:18 ` Greg KH
2012-02-24 17:58 ` David Windsor
2012-02-24 18:37 ` Greg KH
2012-02-24 18:52 ` Kees Cook
2012-02-24 19:05 ` Nick Bowler
2012-02-24 19:13 ` Vasiliy Kulikov
2012-02-24 19:35 ` Nick Bowler
2012-02-24 21:59 ` PaX Team [this message]
2012-02-24 18:58 ` Vasiliy Kulikov
2012-02-24 19:41 ` Greg KH
2012-02-24 20:04 ` Kees Cook
2012-02-24 19:04 ` David Windsor
2012-02-24 22:14 ` PaX Team
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