From: Rajat Jain Date: Fri, 30 Jul 2021 23:53:04 +0000 (-0700) Subject: thunderbolt: Add authorized value to the KOBJ_CHANGE uevent X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1651d9e7810e79500b4940122e192b8aaeb2d63c;p=linux.git 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=" where 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 Signed-off-by: Mika Westerberg --- diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index 83b1ef3d5d037..bc91887f24c30 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -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); } unlock: