intel_menlow: fix memory leaks in error path

This patch includes below fixes in error path:
1. fix a memory leak if device_create_file failed in
intel_menlow_add_one_attribute
2. properly free added attributes before return error in
intel_menlow_register_sensor error handler
3. properly call acpi_bus_unregister_driver before return error in
intel_menlow_module_init

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

diff --git a/drivers/platform/x86/intel_menlow.c b/drivers/platform/x86/intel_menlow.c
index 2f795ce2b939216274a32a3d740152dbaba09108..eacd5da7dd2434b8475b6e4cc89d9ee6d6145b20 100644 (file)
--- a/drivers/platform/x86/intel_menlow.c
+++ b/drivers/platform/x86/intel_menlow.c
@@ -53,6 +53,8 @@ MODULE_LICENSE("GPL");
 #define MEMORY_ARG_CUR_BANDWIDTH 1
 #define MEMORY_ARG_MAX_BANDWIDTH 0
 
+static void intel_menlow_unregister_sensor(void);
+
 /*
  * GTHS returning 'n' would mean that [0,n-1] states are supported
  * In that case max_cstate would be n-1
@@ -406,8 +408,10 @@ static int intel_menlow_add_one_attribute(char *name, int mode, void *show,
        attr->handle = handle;
 
        result = device_create_file(dev, &attr->attr);
-       if (result)
+       if (result) {
+               kfree(attr);
                return result;
+       }
 
        mutex_lock(&intel_menlow_attr_lock);
        list_add_tail(&attr->node, &intel_menlow_attr_list);
@@ -431,11 +435,11 @@ static acpi_status intel_menlow_register_sensor(acpi_handle handle, u32 lvl,
        /* _TZ must have the AUX0/1 methods */
        status = acpi_get_handle(handle, GET_AUX0, &dummy);
        if (ACPI_FAILURE(status))
-               goto not_found;
+               return (status == AE_NOT_FOUND) ? AE_OK : status;
 
        status = acpi_get_handle(handle, SET_AUX0, &dummy);
        if (ACPI_FAILURE(status))
-               goto not_found;
+               return (status == AE_NOT_FOUND) ? AE_OK : status;
 
        result = intel_menlow_add_one_attribute("aux0", 0644,
                                                aux0_show, aux0_store,
@@ -445,17 +449,19 @@ static acpi_status intel_menlow_register_sensor(acpi_handle handle, u32 lvl,
 
        status = acpi_get_handle(handle, GET_AUX1, &dummy);
        if (ACPI_FAILURE(status))
-               goto not_found;
+               goto aux1_not_found;
 
        status = acpi_get_handle(handle, SET_AUX1, &dummy);
        if (ACPI_FAILURE(status))
-               goto not_found;
+               goto aux1_not_found;
 
        result = intel_menlow_add_one_attribute("aux1", 0644,
                                                aux1_show, aux1_store,
                                                &thermal->device, handle);
-       if (result)
+       if (result) {
+               intel_menlow_unregister_sensor();
                return AE_ERROR;
+       }
 
        /*
         * create the "dabney_enabled" attribute which means the user app
@@ -465,14 +471,17 @@ static acpi_status intel_menlow_register_sensor(acpi_handle handle, u32 lvl,
        result = intel_menlow_add_one_attribute("bios_enabled", 0444,
                                                bios_enabled_show, NULL,
                                                &thermal->device, handle);
-       if (result)
+       if (result) {
+               intel_menlow_unregister_sensor();
                return AE_ERROR;
+       }
 
- not_found:
+ aux1_not_found:
        if (status == AE_NOT_FOUND)
                return AE_OK;
-       else
-               return status;
+
+       intel_menlow_unregister_sensor();
+       return status;
 }
 
 static void intel_menlow_unregister_sensor(void)
@@ -513,8 +522,10 @@ static int __init intel_menlow_module_init(void)
        status = acpi_walk_namespace(ACPI_TYPE_THERMAL, ACPI_ROOT_OBJECT,
                                     ACPI_UINT32_MAX,
                                     intel_menlow_register_sensor, NULL, NULL, NULL);
-       if (ACPI_FAILURE(status))
+       if (ACPI_FAILURE(status)) {
+               acpi_bus_unregister_driver(&intel_menlow_memory_driver);
                return -ENODEV;
+       }
 
        return 0;
 }