For security, 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: Rajat Jain <rajatja@xxxxxxxxxx> --- drivers/thunderbolt/switch.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index 83b1ef3d5d03..382128dfbdee 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -1499,6 +1499,7 @@ static ssize_t authorized_show(struct device *dev, static int disapprove_switch(struct device *dev, void *not_used) { struct tb_switch *sw; + char *envp[] = { "AUTHORIZED=0", NULL }; sw = tb_to_switch(dev); if (sw && sw->authorized) { @@ -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; @@ -1523,6 +1524,8 @@ static int disapprove_switch(struct device *dev, void *not_used) static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val) { int ret = -EINVAL; + char envp_string[13]; + char *envp[] = { envp_string, NULL }; if (!mutex_trylock(&sw->tb->lock)) return restart_syscall(); @@ -1560,7 +1563,8 @@ 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); + sprintf(envp_string, "AUTHORIZED=%u", sw->authorized); + kobject_uevent_env(&sw->dev.kobj, KOBJ_CHANGE, envp); } unlock: -- 2.32.0.432.gabb21c7263-goog