rtc: 88pm860x: fix possible race condition (9cf4789e) · Commits · 戴 / test

The RTC IRQ is requested before the struct rtc_device is allocated, this may lead to a NULL pointer dereference in the IRQ handler. To fix this issue, allocating the rtc_device struct before requesting the RTC IRQ using devm_rtc_allocate_device, and use rtc_register_device to register the RTC device. Also remove the unnecessary error message as the core already prints the info. Link: https://lore.kernel.org/r/20200311223956.51352-1-alexandre.belloni@bootlin.com Signed-off-by:

Alexandre Belloni <alexandre.belloni@bootlin.com>

drivers/rtc/rtc-88pm860x.c

+8 −6

Original line number	Diff line number	Diff line
		@@ -336,6 +336,10 @@ static int pm860x_rtc_probe(struct platform_device *pdev)
		info->dev = &pdev->dev;
		dev_set_drvdata(&pdev->dev, info);

		info->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
		if (IS_ERR(info->rtc_dev))
		return PTR_ERR(info->rtc_dev);

		ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
		rtc_update_handler, IRQF_ONESHOT, "rtc",
		info);
		@@ -377,13 +381,11 @@ static int pm860x_rtc_probe(struct platform_device *pdev)
		}
		}

		info->rtc_dev = devm_rtc_device_register(&pdev->dev, "88pm860x-rtc",
		&pm860x_rtc_ops, THIS_MODULE);
		ret = PTR_ERR(info->rtc_dev);
		if (IS_ERR(info->rtc_dev)) {
		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
		info->rtc_dev->ops = &pm860x_rtc_ops;

		ret = rtc_register_device(info->rtc_dev);
		if (ret)
		return ret;
		}

		/*
		* enable internal XO instead of internal 3.25MHz clock since it can

Admin message