Today the pci_dev->untrusted is set for any devices sitting downstream
an external facing port (determined via "ExternalFacingPort" property).
This however, disallows any internal devices to be marked as untrusted.
There are use-cases though, where a platform would like to treat an
internal device as untrusted (perhaps because it runs untrusted
firmware, or offers an attack surface by handling untrusted network
data etc).
This patch introduces a new "UntrustedDevice" property that can be used
by the firmware to mark any device as untrusted.
Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx>
---
drivers/pci/pci-acpi.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index a42dbf448860..3d9e5fa49451 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -1350,12 +1350,25 @@ static void pci_acpi_set_external_facing(struct pci_dev *dev)
dev->external_facing = 1;
}
+static void pci_acpi_set_untrusted(struct pci_dev *dev)
+{
+ u8 val;
+
+ if (device_property_read_u8(&dev->dev, "UntrustedDevice", &val))
+ return;
+
+ /* These PCI devices are not trustworthy */
+ if (val)
+ dev->untrusted = 1;
+}
+
void pci_acpi_setup(struct device *dev, struct acpi_device *adev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
pci_acpi_optimize_delay(pci_dev, adev->handle);
pci_acpi_set_external_facing(pci_dev);
+ pci_acpi_set_untrusted(pci_dev);
pci_acpi_add_edr_notifier(pci_dev);
pci_acpi_add_pm_notifier(adev, pci_dev);
--
2.34.1.703.g22d0c6ccf7-goog
