diff options
| author |   Alexandre Belloni <alexandre.belloni@bootlin.com> | 2019-04-16 10:30:43 +0200 |
|---|---|---|
| committer | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2019-04-29 15:53:42 +0200 |
| commit | ebc2ec4ecf1893b9afaecc59fbd04b2bdf34f7c2 (patch) | |
| tree | 128a206c66821335fe30f285d5a97b0cdc6b47a2 /drivers/rtc | |
| parent | rtc: stm32: manage the get_irq probe defer case (diff) | |
| download | linux-dev-ebc2ec4ecf1893b9afaecc59fbd04b2bdf34f7c2.tar.xz linux-dev-ebc2ec4ecf1893b9afaecc59fbd04b2bdf34f7c2.zip | |
rtc: mxc: 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.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/rtc-mxc.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c index 708b9e9b86a6..d9a038afedf0 100644 --- a/drivers/rtc/rtc-mxc.c +++ b/drivers/rtc/rtc-mxc.c @@ -340,6 +340,13 @@ static int mxc_rtc_probe(struct platform_device *pdev) if (IS_ERR(pdata->ioaddr)) return PTR_ERR(pdata->ioaddr); + rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + pdata->rtc = rtc; + rtc->ops = &mxc_rtc_ops; + pdata->clk_ipg = devm_clk_get(&pdev->dev, "ipg"); if (IS_ERR(pdata->clk_ipg)) { dev_err(&pdev->dev, "unable to get ipg clock!\n"); @@ -402,14 +409,9 @@ static int mxc_rtc_probe(struct platform_device *pdev) dev_err(&pdev->dev, "failed to enable irq wake\n"); } - rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &mxc_rtc_ops, - THIS_MODULE); - if (IS_ERR(rtc)) { - ret = PTR_ERR(rtc); + ret = rtc_register_device(rtc); + if (ret) goto exit_put_clk_ref; - } - - pdata->rtc = rtc; return 0; |