[PATCH 1/2] rtc: zynqmp: fix possible race condition
From: Alexandre Belloni <alexandre.belloni@bootlin.com>
Date: 2019-03-03 21:45:22
Subsystem:
real time clock (rtc) subsystem, the rest · Maintainers:
Alexandre Belloni, Linus Torvalds
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. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> --- drivers/rtc/rtc-zynqmp.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/rtc/rtc-zynqmp.c b/drivers/rtc/rtc-zynqmp.c
index c532bd13fbe5..f0dd20785b54 100644
--- a/drivers/rtc/rtc-zynqmp.c
+++ b/drivers/rtc/rtc-zynqmp.c@@ -222,6 +222,12 @@ static int xlnx_rtc_probe(struct platform_device *pdev) platform_set_drvdata(pdev, xrtcdev); + xrtcdev->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(xrtcdev->rtc)) + return PTR_ERR(xrtcdev->rtc); + + xrtcdev->rtc->ops = &xlnx_rtc_ops; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); xrtcdev->reg_base = devm_ioremap_resource(&pdev->dev, res);
@@ -263,9 +269,7 @@ static int xlnx_rtc_probe(struct platform_device *pdev) device_init_wakeup(&pdev->dev, 1); - xrtcdev->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, - &xlnx_rtc_ops, THIS_MODULE); - return PTR_ERR_OR_ZERO(xrtcdev->rtc); + return rtc_register_device(xrtcdev->rtc); } static int xlnx_rtc_remove(struct platform_device *pdev)
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2.20.1