mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Ahmad Fatoum <a.fatoum@pengutronix.de>
To: barebox@lists.infradead.org
Cc: Johannes Zink <j.zink@pengutronix.de>,
	Ahmad Fatoum <a.fatoum@pengutronix.de>
Subject: [PATCH master 1/2] regulator: handle regulator_get_voltage(NULL) gracefully
Date: Mon, 18 Jul 2022 13:48:23 +0200	[thread overview]
Message-ID: <20220718114824.2632364-1-a.fatoum@pengutronix.de> (raw)

Unlike recent versions of Linux, barebox represents the dummy regulator
as a NULL pointer and regulator API is supposed to anticipate operation
on a NULL pointer. When regulator_get_voltage was ported from Linux,
this was not taken into consideration, which leads to
regulator_get_voltage(NULL) crashing with a NULL pointer dereference.

Fix this by returning -EINVAL for dummy regulators. This aligns us with
how Linux would behave in this situation.

Fixes: 6ee83ce08b24 ("regulator: add regulator_get_voltage() to API")
Reported-by: Johannes Zink <j.zink@pengutronix.de>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 drivers/regulator/core.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 1fb344656f38..472b26f3a0ac 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -574,9 +574,14 @@ EXPORT_SYMBOL_GPL(regulator_bulk_free);
 
 int regulator_get_voltage(struct regulator *regulator)
 {
-	struct regulator_dev *rdev = regulator->ri->rdev;
+	struct regulator_dev *rdev;
 	int sel, ret;
 
+	if (!regulator)
+		return -EINVAL;
+
+	rdev = regulator->ri->rdev;
+
 	if (rdev->desc->ops->get_voltage_sel) {
 		sel = rdev->desc->ops->get_voltage_sel(rdev);
 		if (sel < 0)
-- 
2.30.2




             reply	other threads:[~2022-07-18 11:50 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-18 11:48 Ahmad Fatoum [this message]
2022-07-18 11:48 ` [PATCH master 2/2] common: don't fixup empty serial/machine_compatible strings Ahmad Fatoum
2022-08-08 14:21 ` [PATCH master 1/2] regulator: handle regulator_get_voltage(NULL) gracefully Sascha Hauer

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=20220718114824.2632364-1-a.fatoum@pengutronix.de \
    --to=a.fatoum@pengutronix.de \
    --cc=barebox@lists.infradead.org \
    --cc=j.zink@pengutronix.de \
    --subject='Re: [PATCH master 1/2] regulator: handle regulator_get_voltage(NULL) gracefully' \
    /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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox