Commit Graph

14 Commits

Author SHA1 Message Date
Samuel Ortiz
664431ff14 vsock: vhost_user: vfio: Fix potential host memory overflow
The vsock packets that we're building are resolving guest addresses to
host ones and use the latter as raw pointers.
If the corresponding guest mapped buffer spans across several regions in
the guest, they will do so in the host as well. Since we have no
guarantees that host regions are contiguous, it may lead the VMM into
trying to access memory outside of its memory space.

For now we fix that by ensuring that the guest buffers do not span
across several regions. If they do, we error out.
Ideally, we should enhance the rust-vmm memory model to support safe
acces across host regions.

Fixes CVE-2019-18960

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2019-12-12 22:15:50 +01:00
Wu Zongyong
1dfd60b609 vfio: use correct flags to disable interrupts
The comments of vfio kernel module said that individual subindex
interrupts can be disabled using the -1 value for DATA_EVENTFD or
the index can be disabled as a whole with:
    flags = (DATA_NONE|ACTION_TRIGGER), count = 0.

Signed-off-by: Wu Zongyong <wuzongyong@linux.alibaba.com>
CC: Liu Jiang <gerry@linux.alibaba.com>
2019-12-04 14:47:06 +00:00
Samuel Ortiz
0f21781fbe cargo: Bump the kvm and vmm-sys-util crates
Since the kvm crates now depend on vmm-sys-util, the bump must be
atomic.
The kvm-bindings and ioctls 0.2.0 and 0.4.0 crates come with a few API
changes, one of them being the use of a kvm_ioctls specific error type.
Porting our code to that type makes for a fairly large diff stat.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2019-11-29 17:48:02 +00:00
Sebastien Boeuf
360f0639f4 Revert "vfio: use correct flags to disable interrupts"
This reverts commit 66fde245b3.

The commit broke the VFIO support for MSI. Issue needs to be
investigated but in the meantime, it is safer to fix the codebase.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2019-11-24 12:43:06 +01:00
Wu Zongyong
66fde245b3 vfio: use correct flags to disable interrupts
The comments of vfio kernel module said that individual subindex
interrupts can be disabled using the -1 value for DATA_EVENTFD or
the index can be disabled as a whole with:
    flags = (DATA_NONE|ACTION_TRIGGER), count = 0.

Signed-off-by: Wu Zongyong <wuzongyong@linux.alibaba.com>
CC: Liu Jiang <gerry@linux.alibaba.com>
2019-11-21 06:38:36 -08:00
Sebastien Boeuf
3acf9dfcf3 vfio: Don't map guest memory for VFIO devices attached to vIOMMU
In case a VFIO devices is being attached behind a virtual IOMMU, we
should not automatically map the entire guest memory for the specific
device.

A VFIO device attached to the virtual IOMMU will be driven with IOVAs,
hence we should simply wait for the requests coming from the virtual
IOMMU.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2019-10-16 07:27:06 +02:00
Sebastien Boeuf
837bcbc6ba vfio: Create VFIO implementation of ExternalDmaMapping
With this implementation of the trait ExternalDmaMapping, we now have
the tool to provide to the virtual IOMMU to trigger the map/unmap on
behalf of the guest.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2019-10-16 07:27:06 +02:00
Sebastien Boeuf
3598e603d5 vfio: Add a public function to retrive VFIO container
The VFIO container is the object needed to update the VFIO mapping
associated with a VFIO device. This patch allows the device manager
to have access to the VFIO container.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2019-10-16 07:27:06 +02:00
Sebastien Boeuf
0b8856d148 vmm: Add RwLock to the GuestMemoryMmap
Following the refactoring of the code allowing multiple threads to
access the same instance of the guest memory, this patch goes one step
further by adding RwLock to it. This anticipates the future need for
being able to modify the content of the guest memory at runtime.

The reasons for adding regions to an existing guest memory could be:
- Add virtio-pmem and virtio-fs regions after the guest memory was
  created.
- Support future hotplug of devices, memory, or anything that would
  require more memory at runtime.

Because most of the time, the lock will be taken as read only, using
RwLock instead of Mutex is the right approach.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2019-08-22 08:24:15 +01:00
Sebastien Boeuf
ec0b5567c8 vmm: Share the guest memory instead of cloning it
The VMM guest memory was cloned (copied) everywhere the code needed to
have ownership of it. In order to clean the code, and in anticipation
for future support of modifying this guest memory instance at runtime,
it is important that every part of the code share the same instance.

Because VirtioDevice implementations need to have access to it from
different threads, that's why Arc must be used in this case.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2019-08-22 08:24:15 +01:00
Rob Bradford
9caad7394d build, misc: Bump vmm-sys-util dependency
The structure of the vmm-sys-util crate has changed with lots of code
moving to submodules.

This change adjusts the use of the imported structs to reference the
submodules.

Fixes: #145

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2019-08-02 07:42:20 -07:00
Sebastien Boeuf
b5eab43aa5 vfio: Create a global KVM VFIO device for all VFIO devices
KVM does not support multiple KVM VFIO devices to be created when
trying to support multiple VFIO devices. This commit creates one
global KVM VFIO device being shared with every VFIO device, which
makes possible the support for passing several devices through the
VM.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2019-07-25 11:45:38 +01:00
Chao Peng
b746dd7116 vfio: Map MMIO regions into the guest
VFIO explictly tells us if a MMIO region can be mapped into the guest
address space or not. Except for MSI-X table BARs, we try to map them
into the guest whenever VFIO allows us to do so. This avoids unnecessary
VM exits when the guest tries to access those regions.

Signed-off-by: Zhang, Xiong Y <xiong.y.zhang@intel.com>
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2019-07-24 11:55:08 +02:00
Samuel Ortiz
2cec3aad7f vfio: VFIO API wrappers and helpers
The Virtual Function I/O (VFIO) kernel subsystem exposes a vast and
relatively complex userspace API. This commit abstracts and simplifies
this API into both an internal and external API.

The external API is to be consumed by VFIO device implementation through
the VfioDevice structure. A VfioDevice instance can:

- Enable and disable all interrupts (INTX, MSI and MSI-X) on the
  underlying VFIO device.
- Read and write all of the VFIO device memory regions.
- Set the system's IOMMU tables for the underlying device.

Signed-off-by: Zhang, Xiong Y <xiong.y.zhang@intel.com>
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2019-07-24 11:55:08 +02:00