[PATCH 6.12.y 1/2] platform/x86: intel_sar: Check ACPI_HANDLE() against NULL

[Sasha Levin <sashal@kernel.org>]

From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>

[ Upstream commit 2765f16c12af7c2533763e46b8113b727354012d ]

Every platform driver can be forced to match a device that doesn't match
its list of device IDs because of device_match_driver_override(), so
platform drivers that rely on the existence of a device's ACPI companion
object need to verify its presence.

Accordingly, add a requisite ACPI_HANDLE() check against NULL to the
platform/x86 intel_sar driver.

Fixes: dcfbd31ef4bc ("platform/x86: BIOS SAR driver for Intel M.2 Modem")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/14023870.uLZWGnKmhe@rafael.j.wysocki
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

For this stable dependency, also convert the existing allocations in
parse_package() and sar_probe() to kmalloc_objs() and kzalloc_obj().
Both helpers are already available in this tree and retain the same
allocation sizes and GFP_KERNEL flags. This makes intel_sar.c match
the parent of 30c906cff490 ("platform/x86: int1092: Fix potential
memory leak in sar_probe()"), allowing that target to apply unchanged.
No new functions or allocation helpers are introduced.

Stable-dep-of: 30c906cff490 ("platform/x86: int1092: Fix potential memory leak in sar_probe()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/platform/x86/intel/int1092/intel_sar.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/platform/x86/intel/int1092/intel_sar.c b/drivers/platform/x86/intel/int1092/intel_sar.c
index 6246c066ade2b..af4c127d33f4d 100644
--- a/drivers/platform/x86/intel/int1092/intel_sar.c
+++ b/drivers/platform/x86/intel/int1092/intel_sar.c
@@ -91,8 +91,8 @@ static acpi_status parse_package(struct wwan_sar_context *context, union acpi_ob
 	    item->package.count <= data->total_dev_mode)
 		return AE_ERROR;
 
-	data->device_mode_info = kmalloc_array(data->total_dev_mode,
-					       sizeof(struct wwan_device_mode_info), GFP_KERNEL);
+	data->device_mode_info = kmalloc_objs(struct wwan_device_mode_info,
+					      data->total_dev_mode);
 	if (!data->device_mode_info)
 		return AE_ERROR;
 
@@ -245,15 +245,20 @@ static void sar_get_data(int reg, struct wwan_sar_context *context)
 static int sar_probe(struct platform_device *device)
 {
 	struct wwan_sar_context *context;
+	acpi_handle handle;
 	int reg;
 	int result;
 
-	context = kzalloc(sizeof(*context), GFP_KERNEL);
+	handle = ACPI_HANDLE(&device->dev);
+	if (!handle)
+		return -ENODEV;
+
+	context = kzalloc_obj(*context);
 	if (!context)
 		return -ENOMEM;
 
 	context->sar_device = device;
-	context->handle = ACPI_HANDLE(&device->dev);
+	context->handle = handle;
 	dev_set_drvdata(&device->dev, context);
 
 	result = guid_parse(SAR_DSM_UUID, &context->guid);
-- 
2.53.0