From: Alexandre Belloni alexandre.belloni@bootlin.com
[ Upstream commit c11af8131a4e7ba1960faed731ee7e84c2c13c94 ]
The RTC IRQ is requested before the struct rtc_device is allocated, this may lead to a NULL pointer dereference in the 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.
Link: https://lore.kernel.org/r/20200306073404.56921-1-alexandre.belloni@bootlin.c... Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/rtc/rtc-ds1374.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/drivers/rtc/rtc-ds1374.c b/drivers/rtc/rtc-ds1374.c index 367497914c100..28eb96cbaf98b 100644 --- a/drivers/rtc/rtc-ds1374.c +++ b/drivers/rtc/rtc-ds1374.c @@ -620,6 +620,10 @@ static int ds1374_probe(struct i2c_client *client, if (!ds1374) return -ENOMEM;
+ ds1374->rtc = devm_rtc_allocate_device(&client->dev); + if (IS_ERR(ds1374->rtc)) + return PTR_ERR(ds1374->rtc); + ds1374->client = client; i2c_set_clientdata(client, ds1374);
@@ -641,12 +645,11 @@ static int ds1374_probe(struct i2c_client *client, device_set_wakeup_capable(&client->dev, 1); }
- ds1374->rtc = devm_rtc_device_register(&client->dev, client->name, - &ds1374_rtc_ops, THIS_MODULE); - if (IS_ERR(ds1374->rtc)) { - dev_err(&client->dev, "unable to register the class device\n"); - return PTR_ERR(ds1374->rtc); - } + ds1374->rtc->ops = &ds1374_rtc_ops; + + ret = rtc_register_device(ds1374->rtc); + if (ret) + return ret;
#ifdef CONFIG_RTC_DRV_DS1374_WDT save_client = client;