FAILED: patch "[PATCH] net: rfkill: gpio: Fix crash due to dereferencering" failed to apply to 6.1-stable tree

FAILED: patch "[PATCH] net: rfkill: gpio: Fix crash due to dereferencering" failed to apply to 6.1-stable tree

[gregkh]

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x b6f56a44e4c1014b08859dcf04ed246500e310e5
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025092155-evacuate-condition-525e@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b6f56a44e4c1014b08859dcf04ed246500e310e5 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hansg@kernel.org>
Date: Sat, 13 Sep 2025 13:35:15 +0200
Subject: [PATCH] net: rfkill: gpio: Fix crash due to dereferencering
 uninitialized pointer

Since commit 7d5e9737efda ("net: rfkill: gpio: get the name and type from
device property") rfkill_find_type() gets called with the possibly
uninitialized "const char *type_name;" local variable.

On x86 systems when rfkill-gpio binds to a "BCM4752" or "LNV4752"
acpi_device, the rfkill->type is set based on the ACPI acpi_device_id:

        rfkill->type = (unsigned)id->driver_data;

and there is no "type" property so device_property_read_string() will fail
and leave type_name uninitialized, leading to a potential crash.

rfkill_find_type() does accept a NULL pointer, fix the potential crash
by initializing type_name to NULL.

Note likely sofar this has not been caught because:

1. Not many x86 machines actually have a "BCM4752"/"LNV4752" acpi_device
2. The stack happened to contain NULL where type_name is stored

Fixes: 7d5e9737efda ("net: rfkill: gpio: get the name and type from device property")
Cc: stable@vger.kernel.org
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hansg@kernel.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://patch.msgid.link/20250913113515.21698-1-hansg@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/rfkill/rfkill-gpio.c b/net/rfkill/rfkill-gpio.c
index 41e657e97761..cf2dcec6ce5a 100644
--- a/net/rfkill/rfkill-gpio.c
+++ b/net/rfkill/rfkill-gpio.c
@@ -94,10 +94,10 @@ static const struct dmi_system_id rfkill_gpio_deny_table[] = {
 static int rfkill_gpio_probe(struct platform_device *pdev)
 {
 	struct rfkill_gpio_data *rfkill;
-	struct gpio_desc *gpio;
+	const char *type_name = NULL;
 	const char *name_property;
 	const char *type_property;
-	const char *type_name;
+	struct gpio_desc *gpio;
 	int ret;
 
 	if (dmi_check_system(rfkill_gpio_deny_table))

[PATCH 6.1.y 1/2] net: rfkill: gpio: add DT support

[Sasha Levin]

From: Philipp Zabel <p.zabel@pengutronix.de>

[ Upstream commit d64c732dfc9edcd57feb693c23162117737e426b ]

Allow probing rfkill-gpio via device tree. This hooks up the already
existing support that was started in commit 262c91ee5e52 ("net:
rfkill: gpio: prepare for DT and ACPI support") via the "rfkill-gpio"
compatible, with the "name" and "type" properties renamed to "label"
and "radio-type", respectively, in the device tree case.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20230102-rfkill-gpio-dt-v2-2-d1b83758c16d@pengutronix.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Stable-dep-of: b6f56a44e4c1 ("net: rfkill: gpio: Fix crash due to dereferencering uninitialized pointer")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rfkill/rfkill-gpio.c | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/net/rfkill/rfkill-gpio.c b/net/rfkill/rfkill-gpio.c
index 2df5bf240b64a..ecfb766c47d08 100644
--- a/net/rfkill/rfkill-gpio.c
+++ b/net/rfkill/rfkill-gpio.c
@@ -79,6 +79,8 @@ static int rfkill_gpio_probe(struct platform_device *pdev)
 {
 	struct rfkill_gpio_data *rfkill;
 	struct gpio_desc *gpio;
+	const char *name_property;
+	const char *type_property;
 	const char *type_name;
 	int ret;
 
@@ -86,8 +88,15 @@ static int rfkill_gpio_probe(struct platform_device *pdev)
 	if (!rfkill)
 		return -ENOMEM;
 
-	device_property_read_string(&pdev->dev, "name", &rfkill->name);
-	device_property_read_string(&pdev->dev, "type", &type_name);
+	if (dev_of_node(&pdev->dev)) {
+		name_property = "label";
+		type_property = "radio-type";
+	} else {
+		name_property = "name";
+		type_property = "type";
+	}
+	device_property_read_string(&pdev->dev, name_property, &rfkill->name);
+	device_property_read_string(&pdev->dev, type_property, &type_name);
 
 	if (!rfkill->name)
 		rfkill->name = dev_name(&pdev->dev);
@@ -169,12 +178,19 @@ static const struct acpi_device_id rfkill_acpi_match[] = {
 MODULE_DEVICE_TABLE(acpi, rfkill_acpi_match);
 #endif
 
+static const struct of_device_id rfkill_of_match[] __maybe_unused = {
+	{ .compatible = "rfkill-gpio", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, rfkill_of_match);
+
 static struct platform_driver rfkill_gpio_driver = {
 	.probe = rfkill_gpio_probe,
 	.remove = rfkill_gpio_remove,
 	.driver = {
 		.name = "rfkill_gpio",
 		.acpi_match_table = ACPI_PTR(rfkill_acpi_match),
+		.of_match_table = of_match_ptr(rfkill_of_match),
 	},
 };
 
-- 
2.51.0

[PATCH 6.1.y 2/2] net: rfkill: gpio: Fix crash due to dereferencering uninitialized pointer

[Sasha Levin]

From: Hans de Goede <hansg@kernel.org>

[ Upstream commit b6f56a44e4c1014b08859dcf04ed246500e310e5 ]

Since commit 7d5e9737efda ("net: rfkill: gpio: get the name and type from
device property") rfkill_find_type() gets called with the possibly
uninitialized "const char *type_name;" local variable.

On x86 systems when rfkill-gpio binds to a "BCM4752" or "LNV4752"
acpi_device, the rfkill->type is set based on the ACPI acpi_device_id:

        rfkill->type = (unsigned)id->driver_data;

and there is no "type" property so device_property_read_string() will fail
and leave type_name uninitialized, leading to a potential crash.

rfkill_find_type() does accept a NULL pointer, fix the potential crash
by initializing type_name to NULL.

Note likely sofar this has not been caught because:

1. Not many x86 machines actually have a "BCM4752"/"LNV4752" acpi_device
2. The stack happened to contain NULL where type_name is stored

Fixes: 7d5e9737efda ("net: rfkill: gpio: get the name and type from device property")
Cc: stable@vger.kernel.org
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hansg@kernel.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://patch.msgid.link/20250913113515.21698-1-hansg@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rfkill/rfkill-gpio.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/rfkill/rfkill-gpio.c b/net/rfkill/rfkill-gpio.c
index ecfb766c47d08..1a3560cdba3e9 100644
--- a/net/rfkill/rfkill-gpio.c
+++ b/net/rfkill/rfkill-gpio.c
@@ -78,10 +78,10 @@ static int rfkill_gpio_acpi_probe(struct device *dev,
 static int rfkill_gpio_probe(struct platform_device *pdev)
 {
 	struct rfkill_gpio_data *rfkill;
-	struct gpio_desc *gpio;
+	const char *type_name = NULL;
 	const char *name_property;
 	const char *type_property;
-	const char *type_name;
+	struct gpio_desc *gpio;
 	int ret;
 
 	rfkill = devm_kzalloc(&pdev->dev, sizeof(*rfkill), GFP_KERNEL);
-- 
2.51.0