From 060711f5274dfc2d76a5b2cd65abf6ccbf061e40 Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Tue, 30 Apr 2019 11:32:09 +0200 Subject: [PATCH] rtc: digicolor: 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 struct before requesting the IRQ. Acked-by: Baruch Siach Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-digicolor.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/rtc/rtc-digicolor.c b/drivers/rtc/rtc-digicolor.c index b253bf1b3531..5bb14c56bc9a 100644 --- a/drivers/rtc/rtc-digicolor.c +++ b/drivers/rtc/rtc-digicolor.c @@ -192,6 +192,10 @@ static int __init dc_rtc_probe(struct platform_device *pdev) if (IS_ERR(rtc->regs)) return PTR_ERR(rtc->regs); + rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc->rtc_dev)) + return PTR_ERR(rtc->rtc_dev); + irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; @@ -200,12 +204,10 @@ static int __init dc_rtc_probe(struct platform_device *pdev) return ret; platform_set_drvdata(pdev, rtc); - rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, pdev->name, - &dc_rtc_ops, THIS_MODULE); - if (IS_ERR(rtc->rtc_dev)) - return PTR_ERR(rtc->rtc_dev); - return 0; + rtc->rtc_dev->ops = &dc_rtc_ops; + + return rtc_register_device(rtc->rtc_dev); } static const struct of_device_id dc_dt_ids[] = {