diff options
| author | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2018-09-09 22:38:46 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-11-20 17:59:51 +0100 |
| commit | 9a7a5487408d0d0fb4a269085f36f1129f3b8538 (patch) | |
| tree | 6da2161ae84b6a317d128b497dc790962428da3d | |
| parent | 0d533e3681c79ffa1dcbc4c97535b61fda878d37 (diff) | |
rtc: mt6397: fix possible race condition
[ 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@mediatek.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/rtc/rtc-mt6397.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/drivers/rtc/rtc-mt6397.c b/drivers/rtc/rtc-mt6397.c index 1a61fa56f3ad..e82df43e5ca2 100644 --- a/drivers/rtc/rtc-mt6397.c +++ b/drivers/rtc/rtc-mt6397.c @@ -333,6 +333,10 @@ 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, @@ -345,11 +349,11 @@ 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; } @@ -366,7 +370,6 @@ 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); |