[PATCH 4.18 054/228] platform/x86: asus-wireless: Fix uninitialized symbol usage

From: Greg Kroah-Hartman
Date: Tue Oct 02 2018 - 09:27:25 EST


4.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: JoÃo Paulo Rechi Vita <jprvita@xxxxxxxxxxxx>

[ Upstream commit eca4c4e47eb0658ad251f0bff465e23c055377da ]

'ret' will not be initialized if acpi_evaluate_integer() returns through
an error path, so it should not be used in this case. This fixes the
following Smatch static analyser error:

drivers/platform/x86/asus-wireless.c:76 asus_wireless_method() error:
uninitialized symbol 'ret'.

Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: JoÃo Paulo Rechi Vita <jprvita@xxxxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/platform/x86/asus-wireless.c | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)

--- a/drivers/platform/x86/asus-wireless.c
+++ b/drivers/platform/x86/asus-wireless.c
@@ -52,13 +52,12 @@ static const struct acpi_device_id devic
};
MODULE_DEVICE_TABLE(acpi, device_ids);

-static u64 asus_wireless_method(acpi_handle handle, const char *method,
- int param)
+static acpi_status asus_wireless_method(acpi_handle handle, const char *method,
+ int param, u64 *ret)
{
struct acpi_object_list p;
union acpi_object obj;
acpi_status s;
- u64 ret;

acpi_handle_debug(handle, "Evaluating method %s, parameter %#x\n",
method, param);
@@ -67,24 +66,27 @@ static u64 asus_wireless_method(acpi_han
p.count = 1;
p.pointer = &obj;

- s = acpi_evaluate_integer(handle, (acpi_string) method, &p, &ret);
+ s = acpi_evaluate_integer(handle, (acpi_string) method, &p, ret);
if (ACPI_FAILURE(s))
acpi_handle_err(handle,
"Failed to eval method %s, param %#x (%d)\n",
method, param, s);
- acpi_handle_debug(handle, "%s returned %#llx\n", method, ret);
- return ret;
+ else
+ acpi_handle_debug(handle, "%s returned %#llx\n", method, *ret);
+
+ return s;
}

static enum led_brightness led_state_get(struct led_classdev *led)
{
struct asus_wireless_data *data;
- int s;
+ acpi_status s;
+ u64 ret;

data = container_of(led, struct asus_wireless_data, led);
s = asus_wireless_method(acpi_device_handle(data->adev), "HSWC",
- data->hswc_params->status);
- if (s == data->hswc_params->on)
+ data->hswc_params->status, &ret);
+ if (ACPI_SUCCESS(s) && ret == data->hswc_params->on)
return LED_FULL;
return LED_OFF;
}
@@ -92,10 +94,11 @@ static enum led_brightness led_state_get
static void led_state_update(struct work_struct *work)
{
struct asus_wireless_data *data;
+ u64 ret;

data = container_of(work, struct asus_wireless_data, led_work);
asus_wireless_method(acpi_device_handle(data->adev), "HSWC",
- data->led_state);
+ data->led_state, &ret);
}

static void led_state_set(struct led_classdev *led, enum led_brightness value)