diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-thunderbolt | 20 | ||||
| -rw-r--r-- | Documentation/admin-guide/thunderbolt.rst | 16 | ||||
| -rw-r--r-- | drivers/thunderbolt/domain.c | 32 | ||||
| -rw-r--r-- | drivers/thunderbolt/switch.c | 34 | ||||
| -rw-r--r-- | drivers/thunderbolt/tb.c | 20 | ||||
| -rw-r--r-- | drivers/thunderbolt/tb.h | 3 |
6 files changed, 118 insertions, 7 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-thunderbolt b/Documentation/ABI/testing/sysfs-bus-thunderbolt index a91b4b24496e..581dea95245b 100644 --- a/Documentation/ABI/testing/sysfs-bus-thunderbolt +++ b/Documentation/ABI/testing/sysfs-bus-thunderbolt @@ -49,6 +49,15 @@ Description: Holds a comma separated list of device unique_ids that If a device is authorized automatically during boot its boot attribute is set to 1. +What: /sys/bus/thunderbolt/devices/.../domainX/deauthorization +Date: May 2021 +KernelVersion: 5.12 +Contact: Mika Westerberg <mika.westerberg@linux.intel.com> +Description: This attribute tells whether the system supports + de-authorization of devices. Value of 1 means user can + de-authorize PCIe tunnel by writing 0 to authorized + attribute under each device. + What: /sys/bus/thunderbolt/devices/.../domainX/iommu_dma_protection Date: Mar 2019 KernelVersion: 4.21 @@ -84,22 +93,25 @@ KernelVersion: 4.13 Contact: thunderbolt-software@lists.01.org Description: This attribute is used to authorize Thunderbolt devices after they have been connected. If the device is not - authorized, no devices such as PCIe and Display port are - available to the system. + authorized, no PCIe devices are available to the system. Contents of this attribute will be 0 when the device is not yet authorized. Possible values are supported: - == =========================================== + == =================================================== + 0 The device will be de-authorized (only supported if + deauthorization attribute under domain contains 1) 1 The device will be authorized and connected - == =========================================== + == =================================================== When key attribute contains 32 byte hex string the possible values are: == ======================================================== + 0 The device will be de-authorized (only supported if + deauthorization attribute under domain contains 1) 1 The 32 byte hex string is added to the device NVM and the device is authorized. 2 Send a challenge based on the 32 byte hex string. If the diff --git a/Documentation/admin-guide/thunderbolt.rst b/Documentation/admin-guide/thunderbolt.rst index 613cb24c76c7..0d4348445f91 100644 --- a/Documentation/admin-guide/thunderbolt.rst +++ b/Documentation/admin-guide/thunderbolt.rst @@ -153,6 +153,22 @@ If the user still wants to connect the device they can either approve the device without a key or write a new key and write 1 to the ``authorized`` file to get the new key stored on the device NVM. +De-authorizing devices +---------------------- +It is possible to de-authorize devices by writing ``0`` to their +``authorized`` attribute. This requires support from the connection +manager implementation and can be checked by reading domain +``deauthorization`` attribute. If it reads ``1`` then the feature is +supported. + +When a device is de-authorized the PCIe tunnel from the parent device +PCIe downstream (or root) port to the device PCIe upstream port is torn +down. This is essentially the same thing as PCIe hot-remove and the PCIe +toplogy in question will not be accessible anymore until the device is +authorized again. If there is storage such as NVMe or similar involved, +there is a risk for data loss if the filesystem on that storage is not +properly shut down. You have been warned! + DMA protection utilizing IOMMU ------------------------------ Recent systems from 2018 and forward with Thunderbolt ports may natively diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c index d2b92a8be577..9ba2181464cc 100644 --- a/drivers/thunderbolt/domain.c +++ b/drivers/thunderbolt/domain.c @@ -238,6 +238,16 @@ err_free_str: } static DEVICE_ATTR_RW(boot_acl); +static ssize_t deauthorization_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + const struct tb *tb = container_of(dev, struct tb, dev); + + return sprintf(buf, "%d\n", !!tb->cm_ops->disapprove_switch); +} +static DEVICE_ATTR_RO(deauthorization); + static ssize_t iommu_dma_protection_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -267,6 +277,7 @@ static DEVICE_ATTR_RO(security); static struct attribute *domain_attrs[] = { &dev_attr_boot_acl.attr, + &dev_attr_deauthorization.attr, &dev_attr_iommu_dma_protection.attr, &dev_attr_security.attr, NULL, @@ -602,13 +613,30 @@ int tb_domain_runtime_resume(struct tb *tb) } /** + * tb_domain_disapprove_switch() - Disapprove switch + * @tb: Domain the switch belongs to + * @sw: Switch to disapprove + * + * This will disconnect PCIe tunnel from parent to this @sw. + * + * Return: %0 on success and negative errno in case of failure. + */ +int tb_domain_disapprove_switch(struct tb *tb, struct tb_switch *sw) +{ + if (!tb->cm_ops->disapprove_switch) + return -EPERM; + + return tb->cm_ops->disapprove_switch(tb, sw); +} + +/** * tb_domain_approve_switch() - Approve switch * @tb: Domain the switch belongs to * @sw: Switch to approve * * This will approve switch by connection manager specific means. In - * case of success the connection manager will create tunnels for all - * supported protocols. + * case of success the connection manager will create PCIe tunnel from + * parent to @sw. */ int tb_domain_approve_switch(struct tb *tb, struct tb_switch *sw) { diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index ad992e6204d9..cdba05e72486 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -1387,6 +1387,30 @@ static ssize_t authorized_show(struct device *dev, return sprintf(buf, "%u\n", sw->authorized); } +static int disapprove_switch(struct device *dev, void *not_used) +{ + struct tb_switch *sw; + + sw = tb_to_switch(dev); + if (sw && sw->authorized) { + int ret; + + /* First children */ + ret = device_for_each_child_reverse(&sw->dev, NULL, disapprove_switch); + if (ret) + return ret; + + ret = tb_domain_disapprove_switch(sw->tb, sw); + if (ret) + return ret; + + sw->authorized = 0; + kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE); + } + + return 0; +} + static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val) { int ret = -EINVAL; @@ -1394,10 +1418,18 @@ static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val) if (!mutex_trylock(&sw->tb->lock)) return restart_syscall(); - if (sw->authorized) + if (!!sw->authorized == !!val) goto unlock; switch (val) { + /* Disapprove switch */ + case 0: + if (tb_route(sw)) { + ret = disapprove_switch(&sw->dev, NULL); + goto unlock; + } + break; + /* Approve switch */ case 1: if (sw->key) diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c index 51d5b031cada..d08879849abe 100644 --- a/drivers/thunderbolt/tb.c +++ b/drivers/thunderbolt/tb.c @@ -1002,6 +1002,25 @@ static void tb_disconnect_and_release_dp(struct tb *tb) } } +static int tb_disconnect_pci(struct tb *tb, struct tb_switch *sw) +{ + struct tb_tunnel *tunnel; + struct tb_port *up; + + up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP); + if (WARN_ON(!up)) + return -ENODEV; + + tunnel = tb_find_tunnel(tb, TB_TUNNEL_PCI, NULL, up); + if (WARN_ON(!tunnel)) + return -ENODEV; + + tb_tunnel_deactivate(tunnel); + list_del(&tunnel->list); + tb_tunnel_free(tunnel); + return 0; +} + static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw) { struct tb_port *up, *down, *port; @@ -1512,6 +1531,7 @@ static const struct tb_cm_ops tb_cm_ops = { .runtime_suspend = tb_runtime_suspend, .runtime_resume = tb_runtime_resume, .handle_event = tb_handle_event, + .disapprove_switch = tb_disconnect_pci, .approve_switch = tb_tunnel_pci, .approve_xdomain_paths = tb_approve_xdomain_paths, .disconnect_xdomain_paths = tb_disconnect_xdomain_paths, diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h index 34ae83b9e52a..31468de658e4 100644 --- a/drivers/thunderbolt/tb.h +++ b/drivers/thunderbolt/tb.h @@ -361,6 +361,7 @@ struct tb_path { * @handle_event: Handle thunderbolt event * @get_boot_acl: Get boot ACL list * @set_boot_acl: Set boot ACL list + * @disapprove_switch: Disapprove switch (disconnect PCIe tunnel) * @approve_switch: Approve switch * @add_switch_key: Add key to switch * @challenge_switch_key: Challenge switch using key @@ -394,6 +395,7 @@ struct tb_cm_ops { const void *buf, size_t size); int (*get_boot_acl)(struct tb *tb, uuid_t *uuids, size_t nuuids); int (*set_boot_acl)(struct tb *tb, const uuid_t *uuids, size_t nuuids); + int (*disapprove_switch)(struct tb *tb, struct tb_switch *sw); int (*approve_switch)(struct tb *tb, struct tb_switch *sw); int (*add_switch_key)(struct tb *tb, struct tb_switch *sw); int (*challenge_switch_key)(struct tb *tb, struct tb_switch *sw, @@ -629,6 +631,7 @@ int tb_domain_thaw_noirq(struct tb *tb); void tb_domain_complete(struct tb *tb); int tb_domain_runtime_suspend(struct tb *tb); int tb_domain_runtime_resume(struct tb *tb); +int tb_domain_disapprove_switch(struct tb *tb, struct tb_switch *sw); int tb_domain_approve_switch(struct tb *tb, struct tb_switch *sw); int tb_domain_approve_switch_key(struct tb *tb, struct tb_switch *sw); int tb_domain_challenge_switch_key(struct tb *tb, struct tb_switch *sw); |