From 5490a1e018a4b447c1fdb49ec274a620e60a4d42 Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Sat, 19 May 2018 10:01:42 +0200 Subject: rtc: mxc_v2: fix possible race condition 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. Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-mxc_v2.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'drivers/rtc/rtc-mxc_v2.c') diff --git a/drivers/rtc/rtc-mxc_v2.c b/drivers/rtc/rtc-mxc_v2.c index 9e14efb990b2..4cc121a41fe0 100644 --- a/drivers/rtc/rtc-mxc_v2.c +++ b/drivers/rtc/rtc-mxc_v2.c @@ -343,6 +343,12 @@ static int mxc_rtc_probe(struct platform_device *pdev) return ret; } + pdata->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(pdata->rtc)) + return PTR_ERR(pdata->rtc); + + pdata->rtc->ops = &mxc_rtc_ops; + clk_disable(pdata->clk); platform_set_drvdata(pdev, pdata); ret = @@ -354,15 +360,11 @@ static int mxc_rtc_probe(struct platform_device *pdev) return ret; } - pdata->rtc = - devm_rtc_device_register(&pdev->dev, pdev->name, &mxc_rtc_ops, - THIS_MODULE); - if (IS_ERR(pdata->rtc)) { + ret = rtc_register_device(pdata->rtc); + if (ret < 0) clk_unprepare(pdata->clk); - return PTR_ERR(pdata->rtc); - } - return 0; + return ret; } static int mxc_rtc_remove(struct platform_device *pdev) -- cgit v1.2.3