From: Eric Dumazet <eric.dumazet@gmail.com>
To: David Laight <David.Laight@ACULAB.COM>
Cc: David Miller <davem@davemloft.net>,
netdev <netdev@vger.kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
linux-kernel@vger.kernel.org
Subject: RE: [PATCH net-next] x86: bpf_jit_comp: secure bpf jit against spraying attacks
Date: Mon, 20 May 2013 06:34:53 -0700 [thread overview]
Message-ID: <1369056893.3301.160.camel@edumazet-glaptop> (raw)
In-Reply-To: <AE90C24D6B3A694183C094C60CF0A2F6026B723E@saturn3.aculab.com>
On Mon, 2013-05-20 at 09:51 +0100, David Laight wrote:
> Hmmm.... anyone looking to overwrite kernel code will then start
> looking for blocks of 0xcc bytes and know that what follows
> is the beginning of a function.
> That isn't any harder than random writes.
>
> Copying a random part of .rodata might be better - especially
> if you can find part of .rodata.str*.
That's not the point. We want to catch jumps to before/after the code.
An attacker having full access to kernel code in read and write mode has
full power anyway to do whatever he wants.
next prev parent reply other threads:[~2013-05-20 13:34 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-05-18 2:37 [PATCH net-next] x86: bpf_jit_comp: secure bpf jit against spraying attacks Eric Dumazet
2013-05-19 17:02 ` Daniel Borkmann
2013-05-20 6:55 ` David Miller
2013-05-20 6:56 ` David Miller
2013-05-20 8:51 ` David Laight
2013-05-20 9:50 ` Daniel Borkmann
2013-05-20 13:52 ` Eric Dumazet
2013-05-20 13:34 ` Eric Dumazet [this message]
2013-05-20 14:19 ` Florian Westphal
2013-05-20 14:26 ` Eric Dumazet
2013-05-20 14:35 ` David Laight
2013-05-24 17:23 ` Jarkko Sakkinen
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