linux-stable.git/drivers/vhost/vhost.c, branch v5.7

vhost: missing __user tags

2020-05-15T15:36:31+00:00

sparse warns about converting void * to void __user *. This is not new
but only got noticed now that vhost is built on more systems.
This is just a question of __user tags missing in a couple of places,
so fix it up.

Fixes: f88949138058 ("vhost: introduce O(1) vq metadata cache")
Reported-by: kbuild test robot 
Signed-off-by: Michael S. Tsirkin

vhost: factor out IOTLB

2020-04-01T16:06:26+00:00

This patch factors out IOTLB into a dedicated module in order to be
reused by other modules like vringh. User may choose to enable the
automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit
for the case of vhost device IOTLB implementation.

Signed-off-by: Jason Wang 
Link: https://lore.kernel.org/r/20200326140125.19794-4-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin

vhost: allow per device message handler

2020-04-01T16:06:26+00:00

This patch allow device to register its own message handler during
vhost_dev_init(). vDPA device will use it to implement its own DMA
mapping logic.

Signed-off-by: Jason Wang 
Link: https://lore.kernel.org/r/20200326140125.19794-3-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin

vhost, kcov: collect coverage from vhost_worker

2019-12-05T03:44:14+00:00

Add kcov_remote_start()/kcov_remote_stop() annotations to the
vhost_worker() function, which is responsible for processing vhost
works.

Since vhost_worker() threads are spawned per vhost device instance the
common kcov handle is used for kcov_remote_start()/stop() annotations
(see Documentation/dev-tools/kcov.rst for details).  As the result kcov
can now be used to collect coverage from vhost worker threads.

Link: http://lkml.kernel.org/r/e49d5d154e5da6c9ada521d2b7ce10a49ce9f98b.1572366574.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov 
Cc: Alan Stern 
Cc: Alexander Potapenko 
Cc: Anders Roxell 
Cc: Arnd Bergmann 
Cc: David Windsor 
Cc: Dmitry Vyukov 
Cc: Elena Reshetova 
Cc: Greg Kroah-Hartman 
Cc: Jason Wang 
Cc: Marco Elver 
Cc: "Michael S. Tsirkin" 
Cc: Steven Rostedt 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Revert "vhost: block speculation of translated descriptors"

2019-09-14T19:21:51+00:00

This reverts commit a89db445fbd7f1f8457b03759aa7343fa530ef6b.

I was hasty to include this patch, and it breaks the build on 32 bit.
Defence in depth is good but let's do it properly.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin

vhost: make sure log_num < in_num

2019-09-11T19:15:26+00:00

The code assumes log_num < in_num everywhere, and that is true as long as
in_num is incremented by descriptor iov count, and log_num by 1. However
this breaks if there's a zero sized descriptor.

As a result, if a malicious guest creates a vring desc with desc.len = 0,
it may cause the host kernel to crash by overflowing the log array. This
bug can be triggered during the VM migration.

There's no need to log when desc.len = 0, so just don't increment log_num
in this case.

Fixes: 3a4d5c94e959 ("vhost_net: a kernel-level virtio server")
Cc: stable@vger.kernel.org
Reviewed-by: Lidong Chen 
Signed-off-by: ruippan 
Signed-off-by: yongduan 
Acked-by: Michael S. Tsirkin 
Reviewed-by: Tyler Hicks 
Signed-off-by: Michael S. Tsirkin

vhost: block speculation of translated descriptors

2019-09-11T19:15:07+00:00

iovec addresses coming from vhost are assumed to be
pre-validated, but in fact can be speculated to a value
out of range.

Userspace address are later validated with array_index_nospec so we can
be sure kernel info does not leak through these addresses, but vhost
must also not leak userspace info outside the allowed memory table to
guests.

Following the defence in depth principle, make sure
the address is not validated out of node range.

Signed-off-by: Michael S. Tsirkin 
Cc: stable@vger.kernel.org
Acked-by: Jason Wang 
Tested-by: Jason Wang

Revert "vhost: access vq metadata through kernel virtual address"

2019-09-04T11:39:48+00:00

This reverts commit 7f466032dc ("vhost: access vq metadata through
kernel virtual address").  The commit caused a bunch of issues, and
while commit 73f628ec9e ("vhost: disable metadata prefetch
optimization") disabled the optimization it's not nice to keep lots of
dead code around.

Signed-off-by: Michael S. Tsirkin

vhost: Remove unnecessary variable

2019-09-04T10:21:17+00:00

It is unnecessary to use ret variable to return the error
code, just return the error code directly.

Signed-off-by: Yunsheng Lin 
Signed-off-by: Michael S. Tsirkin

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2019-07-17T18:26:09+00:00

Pull virtio, vhost updates from Michael Tsirkin:
 "Fixes, features, performance:

   - new iommu device

   - vhost guest memory access using vmap (just meta-data for now)

   - minor fixes"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-mmio: add error check for platform_get_irq
  scsi: virtio_scsi: Use struct_size() helper
  iommu/virtio: Add event queue
  iommu/virtio: Add probe request
  iommu: Add virtio-iommu driver
  PCI: OF: Initialize dev->fwnode appropriately
  of: Allow the iommu-map property to omit untranslated devices
  dt-bindings: virtio: Add virtio-pci-iommu node
  dt-bindings: virtio-mmio: Add IOMMU description
  vhost: fix clang build warning
  vhost: access vq metadata through kernel virtual address
  vhost: factor out setting vring addr and num
  vhost: introduce helpers to get the size of metadata area
  vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch()
  vhost: fine grain userspace memory accessors
  vhost: generalize adding used elem