diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index 8c7c4583b52d..77abe0ec4043 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -24,6 +24,14 @@ static int acpi_data_get_property_array(const struct acpi_device_data *data, acpi_object_type type, const union acpi_object **obj); +/* + * The GUIDs here are made equivalent to each other in order to avoid extra + * complexity in the properties handling code, with the caveat that the + * kernel will accept certain combinations of GUID and properties that are + * not defined without a warning. For instance if any of the properties + * from different GUID appear in a property list of another, it will be + * accepted by the kernel. Firmware validation tools should catch these. + */ static const guid_t prp_guids[] = { /* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */ GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c, @@ -31,6 +39,9 @@ static const guid_t prp_guids[] = { /* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */ GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3, 0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4), + /* External facing port GUID: efcc06cc-73ac-4bc3-bff0-76143807c389 */ + GUID_INIT(0xefcc06cc, 0x73ac, 0x4bc3, + 0xbf, 0xf0, 0x76, 0x14, 0x38, 0x07, 0xc3, 0x89), }; static const guid_t ads_guid = diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index 921db6f80340..e1949f7efd9c 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -789,6 +789,24 @@ static void pci_acpi_optimize_delay(struct pci_dev *pdev, ACPI_FREE(obj); } +static void pci_acpi_set_untrusted(struct pci_dev *dev) +{ + u8 val; + + if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) + return; + if (device_property_read_u8(&dev->dev, "ExternalFacingPort", &val)) + return; + + /* + * These root ports expose PCIe (including DMA) outside of the + * system so make sure we treat them and everything behind as + * untrusted. + */ + if (val) + dev->untrusted = 1; +} + static void pci_acpi_setup(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); @@ -798,6 +816,7 @@ static void pci_acpi_setup(struct device *dev) return; pci_acpi_optimize_delay(pci_dev, adev->handle); + pci_acpi_set_untrusted(pci_dev); pci_acpi_add_pm_notifier(adev, pci_dev); if (!adev->wakeup.flags.valid) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index b1c05b5054a0..257b9f6f2ebb 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1378,6 +1378,19 @@ static void set_pcie_thunderbolt(struct pci_dev *dev) } } +static void set_pcie_untrusted(struct pci_dev *dev) +{ + struct pci_dev *parent; + + /* + * If the upstream bridge is untrusted we treat this device + * untrusted as well. + */ + parent = pci_upstream_bridge(dev); + if (parent && parent->untrusted) + dev->untrusted = true; +} + /** * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config? * @dev: PCI device @@ -1638,6 +1651,8 @@ int pci_setup_device(struct pci_dev *dev) /* Need to have dev->cfg_size ready */ set_pcie_thunderbolt(dev); + set_pcie_untrusted(dev); + /* "Unknown power state" */ dev->current_state = PCI_UNKNOWN; diff --git a/include/linux/pci.h b/include/linux/pci.h index 11c71c4ecf75..c786a2f27bee 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -396,6 +396,14 @@ struct pci_dev { unsigned int is_hotplug_bridge:1; unsigned int shpc_managed:1; /* SHPC owned by shpchp */ unsigned int is_thunderbolt:1; /* Thunderbolt controller */ + /* + * Devices marked being untrusted are the ones that can potentially + * execute DMA attacks and similar. They are typically connected + * through external ports such as Thunderbolt but not limited to + * that. When an IOMMU is enabled they should be getting full + * mappings to make sure they cannot access arbitrary memory. + */ + unsigned int untrusted:1; unsigned int __aer_firmware_first_valid:1; unsigned int __aer_firmware_first:1; unsigned int broken_intx_masking:1; /* INTx masking can't be used */