(fixing the typo in the email ID for Greg). On Fri, Jul 23, 2021 at 5:40 PM Rajat Jain <rajatja@xxxxxxxxxx> wrote: > > 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 >