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Date: Tue, 6 Oct 2015 16:58:20 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Vlad Zolotarov <vladz@cloudius-systems.com>
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X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26
Cc: dev@dpdk.org, hjk@hansjkoch.de, gregkh@linux-foundation.org,
 linux-kernel@vger.kernel.org
Subject: Re: [dpdk-dev] [PATCH 2/2] uio: new driver to support PCI MSI-X
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On Tue, Oct 06, 2015 at 11:23:11AM +0300, Vlad Zolotarov wrote:
> Michael, how this or any other related patch is related to the problem u r
> describing?
> The above ability is there for years and if memory serves me
> well it was u who wrote uio_pci_generic with this "security flaw".  ;)

I answered all this already.

This patch enables bus mastering, enables MSI or MSI-X, and requires
userspace to map the MSI-X table and read/write the config space.
This means that a single userspace bug is enough to corrupt kernel
memory.

uio_pci_generic does not enable bus mastering or MSI, and
it might be a good idea to have uio_pci_generic block
access to MSI/MSI-X config.
-- 
MST