From: Hans de Goede Date: Sun, 21 Sep 2025 23:46:30 +0000 (-0400) Subject: net: rfkill: gpio: Fix crash due to dereferencering uninitialized pointer X-Git-Tag: v5.10.245~42 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8793e7a8e1b60131a825457174ed6398111daeb7;p=thirdparty%2Fkernel%2Fstable.git net: rfkill: gpio: Fix crash due to dereferencering uninitialized pointer [ 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 Signed-off-by: Hans de Goede Reviewed-by: Heikki Krogerus Link: https://patch.msgid.link/20250913113515.21698-1-hansg@kernel.org Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- 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);