platform/x86: surface3-wmi: Balance locking on error path

There is a possibility that lock will be left acquired.
Consolidate error path under out_free_unlock label.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

diff --git a/drivers/platform/x86/surface3-wmi.c b/drivers/platform/x86/surface3-wmi.c
index 5553b2b..cbf4d83 100644 (file)
--- a/drivers/platform/x86/surface3-wmi.c
+++ b/drivers/platform/x86/surface3-wmi.c
@@ -60,10 +60,10 @@ static DEFINE_MUTEX(s3_wmi_lock);
 
 static int s3_wmi_query_block(const char *guid, int instance, int *ret)
 {
+       struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
        acpi_status status;
        union acpi_object *obj;
-
-       struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+       int error = 0;
 
        mutex_lock(&s3_wmi_lock);
        status = wmi_query_block(guid, instance, &output);
@@ -77,13 +77,14 @@ static int s3_wmi_query_block(const char *guid, int instance, int *ret)
                               obj->type == ACPI_TYPE_BUFFER ?
                                                obj->buffer.length : 0);
                }
-               kfree(obj);
-               return -EINVAL;
+               error = -EINVAL;
+               goto out_free_unlock;
        }
        *ret = obj->integer.value;
+ out_free_unlock:
        kfree(obj);
        mutex_unlock(&s3_wmi_lock);
-       return 0;
+       return error;
 }
 
 static inline int s3_wmi_query_lid(int *ret)