3.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Alexandre Belloni <alexandre.bell...@bootlin.com> [ Upstream commit abfdff44bc38e9e2ef7929f633fb8462632299d4 ] When using RTC_ALM_SET or RTC_WKALM_SET with rtc_wkalrm.enabled not set, rtc_timer_enqueue() is not called and rtc_set_alarm() may succeed but the subsequent RTC_AIE_ON ioctl will fail. RTC_ALM_READ would also fail in that case. Ensure rtc_set_alarm() fails when alarms are not supported to avoid letting programs think the alarms are working for a particular RTC when they are not. Signed-off-by: Alexandre Belloni <alexandre.bell...@bootlin.com> Signed-off-by: Sasha Levin <alexander.le...@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/rtc/interface.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -381,6 +381,11 @@ int rtc_set_alarm(struct rtc_device *rtc { int err; + if (!rtc->ops) + return -ENODEV; + else if (!rtc->ops->set_alarm) + return -EINVAL; + err = rtc_valid_tm(&alarm->time); if (err != 0) return err;