From: Al Viro <viro@ZenIV.linux.org.uk>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Richard Weinberger <richard.weinberger@gmail.com>,
linux-kernel@vger.kernel.org,
Andrew Morton <akpm@linux-foundation.org>,
Kees Cook <keescook@chromium.org>,
linux-arch <linux-arch@vger.kernel.org>,
Ingo Molnar <mingo@kernel.org>,
hpa@zytor.com
Subject: Re: [PATCH] all arches, signal: Move restart_block to struct task_struct
Date: Sun, 26 Oct 2014 17:18:19 +0000 [thread overview]
Message-ID: <20141026171819.GQ7996@ZenIV.linux.org.uk> (raw)
In-Reply-To: <90d5683679179df27ffeef18c3e1010ed4e72695.1414342681.git.luto@amacapital.net>
On Sun, Oct 26, 2014 at 10:02:16AM -0700, Andy Lutomirski wrote:
> If an attacker can cause a controlled kernel stack overflow,
> overwriting the restart block is a very juicy exploit target.
> Moving the restart block to struct task_struct prevents this type of
> exploit.
The hell it does. In a _lot_ of cases current is current_thread_info()->task,
which makes your variant just as vulnerable, in addition to being (slightly)
more costly.
next prev parent reply other threads:[~2014-10-26 17:18 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-26 17:02 [PATCH] all arches, signal: Move restart_block to struct task_struct Andy Lutomirski
2014-10-26 17:18 ` Al Viro [this message]
2014-10-26 17:36 ` Andy Lutomirski
2014-10-26 18:09 ` Al Viro
2014-10-26 18:11 ` H. Peter Anvin
2014-10-27 1:08 ` Andy Lutomirski
2014-10-26 18:38 ` Sam Ravnborg
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