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| author | Yongliang Gao <leonylgao@tencent.com> | 2024-10-11 12:31:53 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-05 13:54:27 +0100 |
| commit | a1f0b4af90cc18b10261ecde56c6a56b22c75bd1 (patch) | |
| tree | 4f00ecd2ba1b141615f46ac52d0560033e551694 | |
| parent | 0ffa3b4cb8574c480b5d14008235c7f3a67e072b (diff) | |
| download | linux-stable-a1f0b4af90cc18b10261ecde56c6a56b22c75bd1.tar.gz linux-stable-a1f0b4af90cc18b10261ecde56c6a56b22c75bd1.zip | |
rtc: check if __rtc_read_time was successful in rtc_timer_do_work()
[ Upstream commit e8ba8a2bc4f60a1065f23d6a0e7cbea945a0f40d ]
If the __rtc_read_time call fails,, the struct rtc_time tm; may contain
uninitialized data, or an illegal date/time read from the RTC hardware.
When calling rtc_tm_to_ktime later, the result may be a very large value
(possibly KTIME_MAX). If there are periodic timers in rtc->timerqueue,
they will continually expire, may causing kernel softlockup.
Fixes: 6610e0893b8b ("RTC: Rework RTC code to use timerqueue for events")
Signed-off-by: Yongliang Gao <leonylgao@tencent.com>
Acked-by: Jingqun Li <jingqunli@tencent.com>
Link: https://lore.kernel.org/r/20241011043153.3788112-1-leonylgao@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/rtc/interface.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index cca650b2e0b9..aaf76406cd7d 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -904,13 +904,18 @@ void rtc_timer_do_work(struct work_struct *work) struct timerqueue_node *next; ktime_t now; struct rtc_time tm; + int err; struct rtc_device *rtc = container_of(work, struct rtc_device, irqwork); mutex_lock(&rtc->ops_lock); again: - __rtc_read_time(rtc, &tm); + err = __rtc_read_time(rtc, &tm); + if (err) { + mutex_unlock(&rtc->ops_lock); + return; + } now = rtc_tm_to_ktime(tm); while ((next = timerqueue_getnext(&rtc->timerqueue))) { if (next->expires > now) |