From: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
[ Upstream commit babab2f86440352d24e76118fdd7d40cab5fd7bf ]
The IRQ is requested before the struct rtc is allocated and registered, but
this struct is used in the IRQ handler. This may lead to a NULL pointer
dereference.
Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc
before requesting the IRQ.
Acked-by: Eddie Huang <eddie.huang@xxxxxxxxxxxx>
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/rtc/rtc-mt6397.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/drivers/rtc/rtc-mt6397.c b/drivers/rtc/rtc-mt6397.c
index 385f8303bb412..e9a25ec4d434f 100644
--- a/drivers/rtc/rtc-mt6397.c
+++ b/drivers/rtc/rtc-mt6397.c
@@ -332,6 +332,10 @@ static int mtk_rtc_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, rtc);
+ rtc->rtc_dev = devm_rtc_allocate_device(rtc->dev);
+ if (IS_ERR(rtc->rtc_dev))
+ return PTR_ERR(rtc->rtc_dev);
+
ret = request_threaded_irq(rtc->irq, NULL,
mtk_rtc_irq_handler_thread,
IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
@@ -344,11 +348,11 @@ static int mtk_rtc_probe(struct platform_device *pdev)
device_init_wakeup(&pdev->dev, 1);
- rtc->rtc_dev = rtc_device_register("mt6397-rtc", &pdev->dev,
- &mtk_rtc_ops, THIS_MODULE);
- if (IS_ERR(rtc->rtc_dev)) {
+ rtc->rtc_dev->ops = &mtk_rtc_ops;
+
+ ret = rtc_register_device(rtc->rtc_dev);
+ if (ret) {
dev_err(&pdev->dev, "register rtc device failed\n");
- ret = PTR_ERR(rtc->rtc_dev);
goto out_free_irq;
}
@@ -365,7 +369,6 @@ static int mtk_rtc_remove(struct platform_device *pdev)
{
struct mt6397_rtc *rtc = platform_get_drvdata(pdev);
- rtc_device_unregister(rtc->rtc_dev);
free_irq(rtc->irq, rtc->rtc_dev);
irq_dispose_mapping(rtc->irq);
--
2.20.1
