ACPI: Limit access to custom_method when the kernel is locked down
authorMatthew Garrett <mjg59@srcf.ucam.org>
Tue, 20 Aug 2019 00:17:50 +0000 (17:17 -0700)
committerJames Morris <jmorris@namei.org>
Tue, 20 Aug 2019 04:54:16 +0000 (21:54 -0700)
commitf474e1486b78ac15322f8a1cda48a32a1deff9d3
treefe775561f6ce6e2a47ec9b837d398e5ab987efdd
parent95f5e95f41dff31b2a4566c5a8975c08a49ae4e3
ACPI: Limit access to custom_method when the kernel is locked down

custom_method effectively allows arbitrary access to system memory, making
it possible for an attacker to circumvent restrictions on module loading.
Disable it if the kernel is locked down.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: linux-acpi@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
drivers/acpi/custom_method.c
include/linux/security.h
security/lockdown/lockdown.c