acer-wmi: fix memory leaks in WMID_set_capabilities and get_wmid_devices

When acpi_evaluate_object() is passed ACPI_ALLOCATE_BUFFER, the caller
must kfree the returned buffer if AE_OK is returned.

The callers of wmi_query_block() pass ACPI_ALLOCATE_BUFFER, and thus must
check its return value before accessing or kfree() on the buffer.

This patch adds a missing kfree(out.pointer) before exit
WMID_set_capabilities() and get_wmid_devices().

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

diff --git a/drivers/platform/x86/acer-wmi.c b/drivers/platform/x86/acer-wmi.c
index dec558e..652ca18 100644 (file)
--- a/drivers/platform/x86/acer-wmi.c
+++ b/drivers/platform/x86/acer-wmi.c
@@ -772,6 +772,7 @@ static acpi_status WMID_set_capabilities(void)
                obj->buffer.length == sizeof(u32)) {
                devices = *((u32 *) obj->buffer.pointer);
        } else {
+               kfree(out.pointer);
                return AE_ERROR;
        }
 
@@ -788,6 +789,7 @@ static acpi_status WMID_set_capabilities(void)
        if (!(devices & 0x20))
                max_brightness = 0x9;
 
+       kfree(out.pointer);
        return status;
 }
 
@@ -1094,6 +1096,7 @@ static u32 get_wmid_devices(void)
        struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
        union acpi_object *obj;
        acpi_status status;
+       u32 devices = 0;
 
        status = wmi_query_block(WMID_GUID2, 1, &out);
        if (ACPI_FAILURE(status))
@@ -1102,10 +1105,11 @@ static u32 get_wmid_devices(void)
        obj = (union acpi_object *) out.pointer;
        if (obj && obj->type == ACPI_TYPE_BUFFER &&
                obj->buffer.length == sizeof(u32)) {
-               return *((u32 *) obj->buffer.pointer);
-       } else {
-               return 0;
+               devices = *((u32 *) obj->buffer.pointer);
        }
+
+       kfree(out.pointer);
+       return devices;
 }
 
 /*