leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

rtc: mxc: fix possible race condition

Browse Source 
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>
This commit is contained in:
Alexandre Belloni 2019-04-16 10:30:43 +02:00
parent cf612c5949
commit ebc2ec4ecf
1 changed files with 9 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
drivers/rtc/rtc-mxc.c
View File

@ -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;