From: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
To: Vegard Nossum <vegard.nossum@gmail.com>
Cc: netdev@vger.kernel.org, Pekka Enberg <penberg@cs.helsinki.fi>,
Ingo Molnar <mingo@elte.hu>,
linux-kernel@vger.kernel.org
Subject: Re: kmemcheck detected possible information leak to userspace?
Date: Tue, 1 Jul 2008 15:21:06 +0400 [thread overview]
Message-ID: <20080701112106.GB17015@2ka.mipt.ru> (raw)
In-Reply-To: <19f34abd0807010352t264fda16g826912a857e88140@mail.gmail.com>
On Tue, Jul 01, 2008 at 12:52:53PM +0200, Vegard Nossum (vegard.nossum@gmail.com) wrote:
> The u means uninitialized. So it seems not to be just the end. But I
> am not sure where the end of the buffer is anyway.
>
> But there is one thing I forgot: Is this memory initialized by DMA? If
> so, the warning is bogus and I will go hide in shame.
It depends on driver, but sufficiently new hardware (or better say any
non-crappy hardware) will do dma transafer just into skb->data.
To catch it you can put kmemcheck hooks into pci_map* and friend
functions.
--
Evgeniy Polyakov
next prev parent reply other threads:[~2008-07-01 11:21 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-07-01 9:16 kmemcheck detected possible information leak to userspace? Vegard Nossum
2008-07-01 10:25 ` Evgeniy Polyakov
2008-07-01 10:52 ` Vegard Nossum
2008-07-01 11:21 ` Evgeniy Polyakov [this message]
2008-07-01 11:47 ` Andi Kleen
2008-07-01 12:08 ` Pekka Enberg
2008-07-01 12:17 ` Vegard Nossum
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