diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-thunderbolt | 3 | ||||
| -rw-r--r-- | Documentation/admin-guide/thunderbolt.rst | 15 | ||||
| -rw-r--r-- | drivers/thunderbolt/domain.c | 7 | ||||
| -rw-r--r-- | include/linux/thunderbolt.h | 4 |
4 files changed, 23 insertions, 6 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-thunderbolt b/Documentation/ABI/testing/sysfs-bus-thunderbolt index 4ed229789852..151584a1f950 100644 --- a/Documentation/ABI/testing/sysfs-bus-thunderbolt +++ b/Documentation/ABI/testing/sysfs-bus-thunderbolt @@ -35,6 +35,9 @@ Description: This attribute holds current Thunderbolt security level minimum. User needs to authorize each device. dponly: Automatically tunnel Display port (and USB). No PCIe tunnels are created. + usbonly: Automatically tunnel USB controller of the + connected Thunderbolt dock (and Display Port). All + PCIe links downstream of the dock are removed. What: /sys/bus/thunderbolt/devices/.../authorized Date: Sep 2017 diff --git a/Documentation/admin-guide/thunderbolt.rst b/Documentation/admin-guide/thunderbolt.rst index 9948ec36a204..35fccba6a9a6 100644 --- a/Documentation/admin-guide/thunderbolt.rst +++ b/Documentation/admin-guide/thunderbolt.rst @@ -21,11 +21,11 @@ vulnerable to DMA attacks. Security levels and how to use them ----------------------------------- Starting with Intel Falcon Ridge Thunderbolt controller there are 4 -security levels available. The reason for these is the fact that the -connected devices can be DMA masters and thus read contents of the host -memory without CPU and OS knowing about it. There are ways to prevent -this by setting up an IOMMU but it is not always available for various -reasons. +security levels available. Intel Titan Ridge added one more security level +(usbonly). The reason for these is the fact that the connected devices can +be DMA masters and thus read contents of the host memory without CPU and OS +knowing about it. There are ways to prevent this by setting up an IOMMU but +it is not always available for various reasons. The security levels are as follows: @@ -52,6 +52,11 @@ The security levels are as follows: USB. No PCIe tunneling is done. In BIOS settings this is typically called *Display Port Only*. + usbonly + The firmware automatically creates tunnels for the USB controller and + Display Port in a dock. All PCIe links downstream of the dock are + removed. + The current security level can be read from ``/sys/bus/thunderbolt/devices/domainX/security`` where ``domainX`` is the Thunderbolt domain the host controller manages. There is typically diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c index ab4b304306f7..6281266b8ec0 100644 --- a/drivers/thunderbolt/domain.c +++ b/drivers/thunderbolt/domain.c @@ -117,6 +117,7 @@ static const char * const tb_security_names[] = { [TB_SECURITY_USER] = "user", [TB_SECURITY_SECURE] = "secure", [TB_SECURITY_DPONLY] = "dponly", + [TB_SECURITY_USBONLY] = "usbonly", }; static ssize_t boot_acl_show(struct device *dev, struct device_attribute *attr, @@ -227,8 +228,12 @@ static ssize_t security_show(struct device *dev, struct device_attribute *attr, char *buf) { struct tb *tb = container_of(dev, struct tb, dev); + const char *name = "unknown"; - return sprintf(buf, "%s\n", tb_security_names[tb->security_level]); + if (tb->security_level < ARRAY_SIZE(tb_security_names)) + name = tb_security_names[tb->security_level]; + + return sprintf(buf, "%s\n", name); } static DEVICE_ATTR_RO(security); diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h index 47251844d064..a3ed26082bc1 100644 --- a/include/linux/thunderbolt.h +++ b/include/linux/thunderbolt.h @@ -45,12 +45,16 @@ enum tb_cfg_pkg_type { * @TB_SECURITY_USER: User approval required at minimum * @TB_SECURITY_SECURE: One time saved key required at minimum * @TB_SECURITY_DPONLY: Only tunnel Display port (and USB) + * @TB_SECURITY_USBONLY: Only tunnel USB controller of the connected + * Thunderbolt dock (and Display Port). All PCIe + * links downstream of the dock are removed. */ enum tb_security_level { TB_SECURITY_NONE, TB_SECURITY_USER, TB_SECURITY_SECURE, TB_SECURITY_DPONLY, + TB_SECURITY_USBONLY, }; /** |