The patch below does not apply to the 5.15-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-5.15.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-familiar-divisible-9535@gregkh' --subject-prefix 'PATCH 5.15.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))