Today the pci_dev->untrusted is set for any devices sitting downstream
an external facing port (determined via "ExternalFacingPort" or the
"external-facing" properties).
However, currently there is no way for 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).
Introduce a new "UntrustedDevice" property that can be used by the
firmware to mark any device as untrusted.
Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx>
---
v2: * Also use the same property for device tree based systems.
* Add documentation (next patch)
drivers/pci/of.c | 2 ++
drivers/pci/pci-acpi.c | 1 +
drivers/pci/pci.c | 9 +++++++++
drivers/pci/pci.h | 2 ++
4 files changed, 14 insertions(+)
diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index cb2e8351c2cc..e8b804664b69 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -24,6 +24,8 @@ void pci_set_of_node(struct pci_dev *dev)
dev->devfn);
if (dev->dev.of_node)
dev->dev.fwnode = &dev->dev.of_node->fwnode;
+
+ pci_set_untrusted(dev);
}
void pci_release_of_node(struct pci_dev *dev)
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index a42dbf448860..2bffbd5c6114 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -1356,6 +1356,7 @@ void pci_acpi_setup(struct device *dev, struct acpi_device *adev)
pci_acpi_optimize_delay(pci_dev, adev->handle);
pci_acpi_set_external_facing(pci_dev);
+ pci_set_untrusted(pci_dev);
pci_acpi_add_edr_notifier(pci_dev);
pci_acpi_add_pm_notifier(adev, pci_dev);
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 9ecce435fb3f..41e887c27004 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -6869,3 +6869,12 @@ static int __init pci_realloc_setup_params(void)
return 0;
}
pure_initcall(pci_realloc_setup_params);
+
+void pci_set_untrusted(struct pci_dev *pdev)
+{
+ u8 val;
+
+ if (!device_property_read_u8(&pdev->dev, "UntrustedDevice", &val)
+ && val)
+ pdev->untrusted = 1;
+}
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 3d60cabde1a1..6c273ce5e0ba 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -761,4 +761,6 @@ static inline pci_power_t mid_pci_get_power_state(struct pci_dev *pdev)
}
#endif
+void pci_set_untrusted(struct pci_dev *pdev);
+
#endif /* DRIVERS_PCI_H */
--
2.35.0.rc2.247.g8bbb082509-goog
