Commit 1651d9e7 authored by Rajat Jain's avatar Rajat Jain Committed by Mika Westerberg
Browse files

thunderbolt: Add authorized value to the KOBJ_CHANGE uevent 



For security reasons, we would like to monitor and track when the
Thunderbolt devices are authorized and deauthorized (i.e. when the
Thunderbolt sysfs "authorized" attribute changes). Currently the
userspace gets a udev change notification when there is a change, but
the state may have changed (again) by the time we look at the authorized
attribute in sysfs. So an authorization event may go unnoticed. Thus
make it easier by informing the actual change (new value of authorized
attribute) in the udev change notification.

The change is included as a key value "authorized=<val>" where <val>
is the new value of sysfs attribute "authorized", and is described at
Documentation/ABI/testing/sysfs-bus-thunderbolt under
/sys/bus/thunderbolt/devices/.../authorized.

Signed-off-by: default avatarRajat Jain <rajatja@google.com>
Signed-off-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
parent c500bee1

drivers/thunderbolt/switch.c

+10 −3
Original line number Diff line number Diff line
@@ -1498,6 +1498,7 @@ static ssize_t authorized_show(struct device *dev, 


static int disapprove_switch(struct device *dev, void *not_used)

{

	char *envp[] = { "AUTHORIZED=0", NULL };

	struct tb_switch *sw;



	sw = tb_to_switch(dev);
@@ -1514,7 +1515,7 @@ static int disapprove_switch(struct device *dev, void *not_used) 
			return ret;



		sw->authorized = 0;

		kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);

		kobject_uevent_env(&sw->dev.kobj, KOBJ_CHANGE, envp);

	}



	return 0;
@@ -1522,7 +1523,9 @@ static int disapprove_switch(struct device *dev, void *not_used) 


static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val)

{

	char envp_string[13];

	int ret = -EINVAL;

	char *envp[] = { envp_string, NULL };



	if (!mutex_trylock(&sw->tb->lock))

		return restart_syscall();
@@ -1559,8 +1562,12 @@ static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val) 


	if (!ret) {

		sw->authorized = val;

		/* Notify status change to the userspace */

		kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);

		/*

		 * Notify status change to the userspace, informing the new

		 * value of /sys/bus/thunderbolt/devices/.../authorized.

		 */

		sprintf(envp_string, "AUTHORIZED=%u", sw->authorized);

		kobject_uevent_env(&sw->dev.kobj, KOBJ_CHANGE, envp);

	}



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