lkml.org 
[lkml]   [2021]   [Jul]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC v2 2/4] hisi_acc_vfio_pci: Override ioctl method to limit BAR2 region size
Date
HiSilicon ACC VF device BAR2 region consists of both functional register
space and migration control register space. From a security point of
view, it's not advisable to export the migration control region to Guest.

Hence, hide the migration region and report only the functional register
space.

Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
---
drivers/vfio/pci/hisi_acc_vfio_pci.c | 42 +++++++++++++++++++++++++++-
1 file changed, 41 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/pci/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisi_acc_vfio_pci.c
index a9e173098ab5..d57cf6d7adaf 100644
--- a/drivers/vfio/pci/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisi_acc_vfio_pci.c
@@ -12,6 +12,46 @@
#include <linux/vfio.h>
#include <linux/vfio_pci_core.h>

+static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int cmd,
+ unsigned long arg)
+{
+ struct vfio_pci_core_device *vdev =
+ container_of(core_vdev, struct vfio_pci_core_device, vdev);
+
+ if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
+ struct pci_dev *pdev = vdev->pdev;
+ struct vfio_region_info info;
+ unsigned long minsz;
+
+ minsz = offsetofend(struct vfio_region_info, offset);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ if (info.index == VFIO_PCI_BAR2_REGION_INDEX) {
+ info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
+
+ /*
+ * ACC VF dev BAR2 region(64K) consists of both functional
+ * register space and migration control register space.
+ * Report only the first 32K(functional region) to Guest.
+ */
+ info.size = pci_resource_len(pdev, info.index) / 2;
+
+ info.flags = VFIO_REGION_INFO_FLAG_READ |
+ VFIO_REGION_INFO_FLAG_WRITE |
+ VFIO_REGION_INFO_FLAG_MMAP;
+
+ return copy_to_user((void __user *)arg, &info, minsz) ?
+ -EFAULT : 0;
+ }
+ }
+ return vfio_pci_core_ioctl(core_vdev, cmd, arg);
+}
+
static int hisi_acc_vfio_pci_open(struct vfio_device *core_vdev)
{
struct vfio_pci_core_device *vdev =
@@ -33,7 +73,7 @@ static const struct vfio_device_ops hisi_acc_vfio_pci_ops = {
.name = "hisi-acc-vfio-pci",
.open = hisi_acc_vfio_pci_open,
.release = vfio_pci_core_release,
- .ioctl = vfio_pci_core_ioctl,
+ .ioctl = hisi_acc_vfio_pci_ioctl,
.read = vfio_pci_core_read,
.write = vfio_pci_core_write,
.mmap = vfio_pci_core_mmap,
--
2.17.1
\
 
 \ /
  Last update: 2021-07-02 12:00    [W:0.464 / U:0.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site