Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1239998
| From | "Michael S. Tsirkin" <mst@redhat.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH v3 1/3] uio: add ioctl support |
| Date | 2015-10-06 00:30 +0200 |
| Message-ID | <qgmqB-3Uq-1@gated-at.bofh.it> (permalink) |
| References | (3 earlier) <qg8xk-HJ-9@gated-at.bofh.it> <qgaz8-3zT-17@gated-at.bofh.it> <qgblw-4JR-25@gated-at.bofh.it> <qgkf7-L5-1@gated-at.bofh.it> <qgmqB-3Uq-3@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Tue, Oct 06, 2015 at 12:43:45AM +0300, Vladislav Zolotarov wrote: > So, like it has already been asked in a different thread I'm going to > ask a rhetorical question: what adding an MSI and MSI-X interrupts support to > uio_pci_generic has to do with security? memory protection is a better term than security. It's very simple: you enable bus mastering and you ask userspace to map all device BARs. One of these BARs holds the address to which device writes to trigger MSI-X interrupt. This is how MSI-X works, internally: from the point of view of PCI it's a memory write. It just so happens that the destination address is in the interrupt controller, that triggers an interrupt. But a bug in this userspace application can corrupt the MSI-X table, which in turn can easily corrupt kernel memory, or unrelated processes's memory. This is in my opinion unacceptable. So you need to be very careful - probably need to reset device before you even enable bus master - prevent userspace from touching msi config - prevent userspace from moving BARs since msi-x config is within a BAR - detect reset and prevent linux from touching device while it's under reset The list goes on and on. This is pretty much what VFIO spent the last 3 years doing, except VFIO also can do IOMMU groups. > What "security threat" does it add > that u don't already have today? Yes, userspace can create this today if it tweaks PCI config space to enable MSI-X, then corrupts the MSI-X table. It's unfortunate that we don't yet prevent this, but at least you need two things to go wrong for this to trigger. The reason, as I tried to point out, is simply that I didn't think uio_pci_generic will be used for these configurations. But there's nothing fundamental here that makes them secure and that therefore makes your patches secure as well. Fixing this to make uio_pci_generic write-protect MSI/MSI-X enable registers sounds kind of reasonable, this shouldn't be too hard. -- MST -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-04 22:50 +0200
[PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-04 22:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Greg KH <gregkh@linuxfoundation.org> - 2015-10-05 05:20 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 09:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Greg KH <gregkh@linuxfoundation.org> - 2015-10-05 11:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 12:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-05 13:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Greg KH <gregkh@linuxfoundation.org> - 2015-10-05 15:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Greg KH <gregkh@linuxfoundation.org> - 2015-10-05 13:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 13:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-05 13:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 14:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-05 10:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Greg KH <gregkh@linuxfoundation.org> - 2015-10-05 11:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-05 12:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 16:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-06 16:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 17:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-06 17:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-06 17:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Alex Williamson <alex.williamson@redhat.com> - 2015-10-06 21:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Stephen Hemminger <stephen@networkplumber.org> - 2015-10-06 23:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Alex Williamson <alex.williamson@redhat.com> - 2015-10-06 23:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-07 10:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-07 10:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-07 10:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-07 09:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-07 18:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-07 23:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Gleb Natapov <gleb@scylladb.com> - 2015-10-08 06:20 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 09:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Gleb Natapov <gleb@scylladb.com> - 2015-10-08 10:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 11:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Gleb Natapov <gleb@scylladb.com> - 2015-10-08 11:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 14:20 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-08 07:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 09:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-08 10:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 11:20 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-08 11:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 14:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Gleb Natapov <gleb@scylladb.com> - 2015-10-08 14:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 15:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Gleb Natapov <gleb@scylladb.com> - 2015-10-08 15:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 18:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Gleb Natapov <gleb@scylladb.com> - 2015-10-08 19:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 19:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Gleb Natapov <gleb@scylladb.com> - 2015-10-08 20:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Greg KH <gregkh@linuxfoundation.org> - 2015-10-08 20:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 10:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Gleb Natapov <gleb@scylladb.com> - 2015-10-08 11:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-08 11:20 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 12:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-08 15:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 16:20 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Alex Williamson <alex.williamson@redhat.com> - 2015-10-08 17:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Alex Williamson <alex.williamson@redhat.com> - 2015-10-07 18:40 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-07 22:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-07 10:00 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-08 10:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 16:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Avi Kivity <avi@scylladb.com> - 2015-10-06 17:30 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Stephen Hemminger <stephen@networkplumber.org> - 2015-10-05 10:50 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 11:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 12:10 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-05 22:20 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 11:20 +0200
Re: [PATCH v3 2/3] uio_pci_generic: add MSI/MSI-X support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-05 21:20 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-04 22:50 +0200
Re: [PATCH v3 1/3] uio: add ioctl support Greg KH <gregkh@linuxfoundation.org> - 2015-10-05 05:10 +0200
Re: [PATCH v3 1/3] uio: add ioctl support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 09:40 +0200
Re: [PATCH v3 1/3] uio: add ioctl support Greg KH <gregkh@linuxfoundation.org> - 2015-10-05 11:50 +0200
Re: [PATCH v3 1/3] uio: add ioctl support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-05 12:40 +0200
Re: [PATCH v3 1/3] uio: add ioctl support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-05 22:10 +0200
Re: [PATCH v3 1/3] uio: add ioctl support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 00:30 +0200
Re: [PATCH v3 1/3] uio: add ioctl support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-06 10:40 +0200
Re: [PATCH v3 1/3] uio: add ioctl support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 16:20 +0200
Re: [PATCH v3 1/3] uio: add ioctl support Gleb Natapov <gleb@scylladb.com> - 2015-10-06 16:40 +0200
Re: [PATCH v3 1/3] uio: add ioctl support "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 17:30 +0200
Re: [PATCH v3 1/3] uio: add ioctl support Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-06 17:40 +0200
Re: [PATCH v3 1/3] uio: add ioctl support Gleb Natapov <gleb@scylladb.com> - 2015-10-06 18:00 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-05 22:00 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-06 10:40 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 16:40 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-06 16:50 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 17:20 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Vlad Zolotarov <vladz@cloudius-systems.com> - 2015-10-06 18:40 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Avi Kivity <avi@cloudius-systems.com> - 2015-10-06 17:20 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-06 17:20 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Gleb Natapov <gleb@scylladb.com> - 2015-10-06 18:10 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Avi Kivity <avi@scylladb.com> - 2015-10-06 18:10 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver Avi Kivity <avi@scylladb.com> - 2015-10-07 12:30 +0200
Re: [PATCH v3 0/3] uio: add MSI/MSI-X support to uio_pci_generic driver "Michael S. Tsirkin" <mst@redhat.com> - 2015-10-07 12:30 +0200
csiph-web