| From | Greg Kroah-Hartman <> | Subject | [PATCH 5.2 105/137] rtc: snvs: fix possible race condition | Date | Sun, 6 Oct 2019 19:21:29 +0200 |
| |
From: Anson Huang <Anson.Huang@nxp.com>
[ 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 <Anson.Huang@nxp.com> Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com> Link: https://lore.kernel.org/r/20190716071858.36750-1-Anson.Huang@nxp.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- 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 7ee673a25fd0a..4f9a107a04277 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; } -- 2.20.1
|