Message ID | 20200817234833.23954-1-digetx@gmail.com (mailing list archive) |
---|---|
State | Superseded, archived |
Headers | show |
Series | [v1] thermal: core: Fix use-after-free in thermal_zone_device_unregister() | expand |
18.08.2020 02:48, Dmitry Osipenko пишет: > The user-after-free bug in thermal_zone_device_unregister() is reported by > KASAN. It happens because struct thermal_zone_device is released during of > device_unregister() invocation, and hence the "tz" variable shouldn't be > touched by thermal_notify_tz_delete(tz->id). > > Fixes: 55cdf0a283b8 ("thermal: core: Add notifications call in the framework") > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/thermal/thermal_core.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c > index 72bf159bcecc..56c355f684df 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -1516,7 +1516,7 @@ EXPORT_SYMBOL_GPL(thermal_zone_device_register); > */ > void thermal_zone_device_unregister(struct thermal_zone_device *tz) > { > - int i; > + int i, tz_id; > const struct thermal_zone_params *tzp; > struct thermal_cooling_device *cdev; > struct thermal_zone_device *pos = NULL; > @@ -1525,6 +1525,7 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) > return; > > tzp = tz->tzp; > + tz_id = tz->id; > > mutex_lock(&thermal_list_lock); > list_for_each_entry(pos, &thermal_tz_list, node) > @@ -1560,14 +1561,13 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) > cancel_delayed_work_sync(&tz->poll_queue); > > thermal_set_governor(tz, NULL); > - Woops, this line wasn't intended to be removed. Let me send a v2. > thermal_remove_hwmon_sysfs(tz); > ida_simple_remove(&thermal_tz_ida, tz->id); > ida_destroy(&tz->ida); > mutex_destroy(&tz->lock); > device_unregister(&tz->device); > > - thermal_notify_tz_delete(tz->id); > + thermal_notify_tz_delete(tz_id); > } > EXPORT_SYMBOL_GPL(thermal_zone_device_unregister); > >
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 72bf159bcecc..56c355f684df 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -1516,7 +1516,7 @@ EXPORT_SYMBOL_GPL(thermal_zone_device_register); */ void thermal_zone_device_unregister(struct thermal_zone_device *tz) { - int i; + int i, tz_id; const struct thermal_zone_params *tzp; struct thermal_cooling_device *cdev; struct thermal_zone_device *pos = NULL; @@ -1525,6 +1525,7 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) return; tzp = tz->tzp; + tz_id = tz->id; mutex_lock(&thermal_list_lock); list_for_each_entry(pos, &thermal_tz_list, node) @@ -1560,14 +1561,13 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) cancel_delayed_work_sync(&tz->poll_queue); thermal_set_governor(tz, NULL); - thermal_remove_hwmon_sysfs(tz); ida_simple_remove(&thermal_tz_ida, tz->id); ida_destroy(&tz->ida); mutex_destroy(&tz->lock); device_unregister(&tz->device); - thermal_notify_tz_delete(tz->id); + thermal_notify_tz_delete(tz_id); } EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
The user-after-free bug in thermal_zone_device_unregister() is reported by KASAN. It happens because struct thermal_zone_device is released during of device_unregister() invocation, and hence the "tz" variable shouldn't be touched by thermal_notify_tz_delete(tz->id). Fixes: 55cdf0a283b8 ("thermal: core: Add notifications call in the framework") Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- drivers/thermal/thermal_core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)