From: Stephen Boyd swboyd@chromium.org
commit 6b6d188aae79a630957aefd88ff5c42af6553ee3 upstream.
The alarmtimer_rtc_add_device() function creates a wakeup source and then tries to grab a module reference. If that fails the function returns early with an error code, but fails to remove the wakeup source.
Cleanup this exit path so there is no dangling wakeup source, which is named 'alarmtime' left allocated which will conflict with another RTC device that may be registered later.
Fixes: 51218298a25e ("alarmtimer: Ensure RTC module is not unloaded") Signed-off-by: Stephen Boyd swboyd@chromium.org Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Douglas Anderson dianders@chromium.org Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200109155910.907-2-swboyd@chromium.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- kernel/time/alarmtimer.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index f4255a6..9eece67 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -91,6 +91,7 @@ static int alarmtimer_rtc_add_device(struct device *dev, unsigned long flags; struct rtc_device *rtc = to_rtc_device(dev); struct wakeup_source *__ws; + int ret = 0;
if (rtcdev) return -EBUSY; @@ -105,8 +106,8 @@ static int alarmtimer_rtc_add_device(struct device *dev, spin_lock_irqsave(&rtcdev_lock, flags); if (!rtcdev) { if (!try_module_get(rtc->owner)) { - spin_unlock_irqrestore(&rtcdev_lock, flags); - return -1; + ret = -1; + goto unlock; }
rtcdev = rtc; @@ -115,11 +116,12 @@ static int alarmtimer_rtc_add_device(struct device *dev, ws = __ws; __ws = NULL; } +unlock: spin_unlock_irqrestore(&rtcdev_lock, flags);
wakeup_source_unregister(__ws);
- return 0; + return ret; }
static inline void alarmtimer_rtc_timer_init(void)