diff options
author | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2020-03-06 10:34:01 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-01 14:14:38 +0300 |
commit | 142513a2e01ad8952bb63034436d7e7f463f9f93 (patch) | |
tree | eff9e45e6c73ac6c1e1d67e96fb008cc82805730 | |
parent | e934a66dc2c109b1dcf8d0a120393981c5799d68 (diff) | |
download | linux-142513a2e01ad8952bb63034436d7e7f463f9f93.tar.xz |
rtc: ds1374: fix possible race condition
[ 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.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | drivers/rtc/rtc-ds1374.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/rtc/rtc-ds1374.c b/drivers/rtc/rtc-ds1374.c index 38a2e9e684df..77a106e90124 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; |