[PATCH V3 00/10] More virtio hardening

Michael S. Tsirkin
Sat, 23 Oct 2021 21:31:23 -0000

On Tue, Oct 19, 2021 at 03:01:42PM +0800, Jason Wang
wrote:
> Hi All:
>
> This series treis to do more hardening for virito.

OK. So patches 7-10 caused a crash in virtio-blk.
I'm close to sure it's patch 10 actually, and forcing
validation seems to fix the crash.
I also suspect it has something to do with the fact that
blk submits requests in the middle of the probe function.

picked up 1-6 for now.


> patch 1 validates the num_queues for virio-blk device.
> patch 2 validates max_nr_ports for virito-console device.
> patch 3-5 harden virtio-pci interrupts to make sure no exepcted
> interrupt handler is tiggered. If this makes sense we can do similar
> things in other transport drivers.
> patch 6-7 validate used ring length.
> patch 8-10 let the driver to validate the used length instead of the
> virtio core when possible.
>
> Smoking test on blk/net with packed=on/off and iommu_platform=on/off.
>
> Please review.
>
> Changes since V2:
> - don't validate max_nr_ports in .validate()
> - fail the probe instead of trying to work when blk/console returns
>   invalid number of queues/ports
> - use READ_ONCE() instead of smp_load_acquire() for checking
>   intx_soft_enabled
> - use "suppress_used_validation" instead of
"validate_used"
>
> Changes since V1:
> - fix and document the memory ordering around the intx_soft_enabled
>   when enabling and disabling INTX interrupt
> - for the driver that can validate the used length, virtio core
>   won't even try to allocate auxilary arrays and validate the used
length
> - tweak the commit log
> - fix typos
>
> Jason Wang (10):
>   virtio-blk: validate num_queues during probe
>   virtio_console: validate max_nr_ports before trying to use it
>   virtio_config: introduce a new .enable_cbs method
>   virtio_pci: harden MSI-X interrupts
>   virtio-pci: harden INTX interrupts
>   virtio_ring: fix typos in vring_desc_extra
>   virtio_ring: validate used buffer length
>   virtio-net: don't let virtio core to validate used length
>   virtio-blk: don't let virtio core to validate used length
>   virtio-scsi: don't let virtio core to validate used buffer length
>
>  drivers/block/virtio_blk.c         |  5 +++
>  drivers/char/virtio_console.c      |  9 +++++
>  drivers/net/virtio_net.c           |  1 +
>  drivers/scsi/virtio_scsi.c         |  1 +
>  drivers/virtio/virtio_pci_common.c | 48 ++++++++++++++++++++----
>  drivers/virtio/virtio_pci_common.h |  7 +++-
>  drivers/virtio/virtio_pci_legacy.c |  5 ++-
>  drivers/virtio/virtio_pci_modern.c |  6 ++-
>  drivers/virtio/virtio_ring.c       | 60 +++++++++++++++++++++++++++++-
>  include/linux/virtio.h             |  2 +
>  include/linux/virtio_config.h      |  6 +++
>  11 files changed, 135 insertions(+), 15 deletions(-)
>
> --
> 2.25.1