diff options
| author | Giovanni Cabiddu <giovanni.cabiddu@intel.com> | 2020-07-27 13:43:40 -0600 |
|---|---|---|
| committer | Alex Williamson <alex.williamson@redhat.com> | 2020-07-27 13:43:40 -0600 |
| commit | 1f97970e6c8e60349b045599f4525608db895009 (patch) | |
| tree | 254dd45f52af7cf395a6214c0cae77325fb16399 | |
| parent | 8b7beaf9f185249f29912b5e2d7bc4147c5c2a6a (diff) | |
vfio/pci: Add device denylist
Add denylist of devices that by default are not probed by vfio-pci.
Devices in this list may be susceptible to untrusted application, even
if the IOMMU is enabled. To be accessed via vfio-pci, the user has to
explicitly disable the denylist.
The denylist can be disabled via the module parameter disable_denylist.
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Fiona Trahe <fiona.trahe@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| -rw-r--r-- | drivers/vfio/pci/vfio_pci.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index dabca0450e6d..f368a3993ac1 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -60,6 +60,10 @@ module_param(enable_sriov, bool, 0644); MODULE_PARM_DESC(enable_sriov, "Enable support for SR-IOV configuration. Enabling SR-IOV on a PF typically requires support of the userspace PF driver, enabling VFs without such support may result in non-functional VFs or PF."); #endif +static bool disable_denylist; +module_param(disable_denylist, bool, 0444); +MODULE_PARM_DESC(disable_denylist, "Disable use of device denylist. Disabling the denylist allows binding to devices with known errata that may lead to exploitable stability or security issues when accessed by untrusted users."); + static inline bool vfio_vga_disabled(void) { #ifdef CONFIG_VFIO_PCI_VGA @@ -69,6 +73,29 @@ static inline bool vfio_vga_disabled(void) #endif } +static bool vfio_pci_dev_in_denylist(struct pci_dev *pdev) +{ + return false; +} + +static bool vfio_pci_is_denylisted(struct pci_dev *pdev) +{ + if (!vfio_pci_dev_in_denylist(pdev)) + return false; + + if (disable_denylist) { + pci_warn(pdev, + "device denylist disabled - allowing device %04x:%04x.\n", + pdev->vendor, pdev->device); + return false; + } + + pci_warn(pdev, "%04x:%04x exists in vfio-pci device denylist, driver probing disallowed.\n", + pdev->vendor, pdev->device); + + return true; +} + /* * Our VGA arbiter participation is limited since we don't know anything * about the device itself. However, if the device is the only VGA device @@ -1856,6 +1883,9 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) struct iommu_group *group; int ret; + if (vfio_pci_is_denylisted(pdev)) + return -EINVAL; + if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL) return -EINVAL; @@ -2345,6 +2375,9 @@ static int __init vfio_pci_init(void) vfio_pci_fill_ids(); + if (disable_denylist) + pr_warn("device denylist disabled.\n"); + return 0; out_driver: |