From: Anson.Huang@nxp.com
To: a.zummo@towertech.it, alexandre.belloni@bootlin.com,
linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Linux-imx@nxp.com
Subject: [PATCH] rtc: snvs: fix possible race condition
Date: Tue, 16 Jul 2019 15:18:58 +0800 [thread overview]
Message-ID: <20190716071858.36750-1-Anson.Huang@nxp.com> (raw)
From: Anson Huang <Anson.Huang@nxp.com>
The RTC IRQ is requested before the struct rtc_device is allocated,
this may lead to a NULL pointer dereference in 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.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
drivers/rtc/rtc-snvs.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/rtc/rtc-snvs.c b/drivers/rtc/rtc-snvs.c
index 7ee673a2..4f9a107 100644
--- a/drivers/rtc/rtc-snvs.c
+++ b/drivers/rtc/rtc-snvs.c
@@ -279,6 +279,10 @@ static int snvs_rtc_probe(struct platform_device *pdev)
if (!data)
return -ENOMEM;
+ data->rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(data->rtc))
+ return PTR_ERR(data->rtc);
+
data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
if (IS_ERR(data->regmap)) {
@@ -343,10 +347,9 @@ static int snvs_rtc_probe(struct platform_device *pdev)
goto error_rtc_device_register;
}
- data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
- &snvs_rtc_ops, THIS_MODULE);
- if (IS_ERR(data->rtc)) {
- ret = PTR_ERR(data->rtc);
+ data->rtc->ops = &snvs_rtc_ops;
+ ret = rtc_register_device(data->rtc);
+ if (ret) {
dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);
goto error_rtc_device_register;
}
--
2.7.4
next reply other threads:[~2019-07-16 7:28 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-16 7:18 Anson.Huang [this message]
2019-07-17 10:54 ` [PATCH] rtc: snvs: fix possible race condition Aisheng Dong
2019-07-17 13:57 ` Anson Huang
2019-07-18 3:08 ` Aisheng Dong
2019-07-18 16:32 ` Trent Piepho
2019-07-19 2:57 ` Anson Huang
2019-07-19 19:04 ` Trent Piepho
2019-07-20 19:55 ` Alexandre Belloni
2019-08-13 9:22 ` Anson Huang
2019-08-29 15:39 ` Alexandre Belloni
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190716071858.36750-1-Anson.Huang@nxp.com \
--to=anson.huang@nxp.com \
--cc=Linux-imx@nxp.com \
--cc=a.zummo@towertech.it \
--cc=alexandre.belloni@bootlin.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rtc@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).