ACPICA: Namespace: add check to avoid null pointer dereference

ACPICA commit 7586a625f9c34c3169efd88470192bf63119e31a

Some ACPICA userspace tools call acpi_ut_subsystem_shutdown() during
cleanup and dereference a null pointer when cleaning up the
namespace.

Link: https://github.com/acpica/acpica/commit/7586a625
Signed-off-by: Erik Schmauss <erik.schmauss@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/acpica/nsalloc.c b/drivers/acpi/acpica/nsalloc.c
index 5470213b8e645986a3c01b5e0e25ce7961d12dc6..6eb63db72249b0291be099310163841f2b59340e 100644 (file)
--- a/drivers/acpi/acpica/nsalloc.c
+++ b/drivers/acpi/acpica/nsalloc.c
@@ -74,6 +74,10 @@ void acpi_ns_delete_node(struct acpi_namespace_node *node)
 
        ACPI_FUNCTION_NAME(ns_delete_node);
 
+       if (!node) {
+               return_VOID;
+       }
+
        /* Detach an object if there is one */
 
        acpi_ns_detach_object(node);