From 1a5f22226ad004e670048b073a935be76b711a49 Mon Sep 17 00:00:00 2001 From: Anson Huang Date: Tue, 16 Jul 2019 15:18:58 +0800 Subject: rtc: snvs: fix possible race condition [ Upstream commit 6fd4fe9b496d9ba3382992ff4fde3871d1b6f63d ] The RTC IRQ is requested before the struct rtc_device is allocated, this may lead to a NULL pointer dereference in 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. Signed-off-by: Anson Huang Reviewed-by: Dong Aisheng Link: https://lore.kernel.org/r/20190716071858.36750-1-Anson.Huang@nxp.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/rtc/rtc-snvs.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/rtc/rtc-snvs.c b/drivers/rtc/rtc-snvs.c index 7ee673a25fd0..4f9a107a0427 100644 --- a/drivers/rtc/rtc-snvs.c +++ b/drivers/rtc/rtc-snvs.c @@ -279,6 +279,10 @@ static int snvs_rtc_probe(struct platform_device *pdev) if (!data) return -ENOMEM; + data->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(data->rtc)) + return PTR_ERR(data->rtc); + data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap"); if (IS_ERR(data->regmap)) { @@ -343,10 +347,9 @@ static int snvs_rtc_probe(struct platform_device *pdev) goto error_rtc_device_register; } - data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, - &snvs_rtc_ops, THIS_MODULE); - if (IS_ERR(data->rtc)) { - ret = PTR_ERR(data->rtc); + data->rtc->ops = &snvs_rtc_ops; + ret = rtc_register_device(data->rtc); + if (ret) { dev_err(&pdev->dev, "failed to register rtc: %d\n", ret); goto error_rtc_device_register; } -- cgit v1.2.3