acpi_memhotplug.c: fix memory leak when memory device is unbound from the module...

We allocate memory to store acpi_memory_info, so we should free it before
freeing mem_device.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Len Brown <lenb@kernel.org>
Cc: "Brown, Len" <len.brown@intel.com>
Cc: Yasuaki ISIMATU <isimatu.yasuaki@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c
index 24c807f966365e78972cd824c292a9bb944d79e8..62c2c74b5d9aa310eeb02175c4cba575c19eda5c 100644 (file)
--- a/drivers/acpi/acpi_memhotplug.c
+++ b/drivers/acpi/acpi_memhotplug.c
@@ -125,12 +125,20 @@ acpi_memory_get_resource(struct acpi_resource *resource, void *context)
        return AE_OK;
 }
 
+static void
+acpi_memory_free_device_resources(struct acpi_memory_device *mem_device)
+{
+       struct acpi_memory_info *info, *n;
+
+       list_for_each_entry_safe(info, n, &mem_device->res_list, list)
+               kfree(info);
+       INIT_LIST_HEAD(&mem_device->res_list);
+}
+
 static int
 acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
 {
        acpi_status status;
-       struct acpi_memory_info *info, *n;
-
 
        if (!list_empty(&mem_device->res_list))
                return 0;
@@ -138,9 +146,7 @@ acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
        status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
                                     acpi_memory_get_resource, mem_device);
        if (ACPI_FAILURE(status)) {
-               list_for_each_entry_safe(info, n, &mem_device->res_list, list)
-                       kfree(info);
-               INIT_LIST_HEAD(&mem_device->res_list);
+               acpi_memory_free_device_resources(mem_device);
                return -EINVAL;
        }
 
@@ -420,6 +426,15 @@ static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
        return;
 }
 
+static void acpi_memory_device_free(struct acpi_memory_device *mem_device)
+{
+       if (!mem_device)
+               return;
+
+       acpi_memory_free_device_resources(mem_device);
+       kfree(mem_device);
+}
+
 static int acpi_memory_device_add(struct acpi_device *device)
 {
        int result;
@@ -472,14 +487,10 @@ static int acpi_memory_device_add(struct acpi_device *device)
 
 static int acpi_memory_device_remove(struct acpi_device *device, int type)
 {
-       struct acpi_memory_device *mem_device = NULL;
-
-
        if (!device || !acpi_driver_data(device))
                return -EINVAL;
 
-       mem_device = acpi_driver_data(device);
-       kfree(mem_device);
+       acpi_memory_device_free(acpi_driver_data(device));
 
        return 0;
 }