On 04/11/2018 09:24 AM, David Howells wrote: > --- > > arch/x86/kernel/setup.c | 2 + > include/linux/kernel.h | 32 +++++++++++++++++++++++ > security/Kconfig | 23 ++++++++++++++++- > security/Makefile | 3 ++ > security/lock_down.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++ > 5 files changed, 124 insertions(+), 1 deletion(-) > create mode 100644 security/lock_down.c > diff --git a/security/Kconfig b/security/Kconfig > index c4302067a3ad..a68e5bdebad5 100644 > --- a/security/Kconfig > +++ b/security/Kconfig > @@ -231,6 +231,28 @@ config STATIC_USERMODEHELPER_PATH > If you wish for all usermode helper programs to be disabled, > specify an empty string here (i.e. ""). > > +config LOCK_DOWN_KERNEL > + bool "Allow the kernel to be 'locked down'" > + help > + Allow the kernel to be locked down. Locking down the kernel turns > + off various features that might otherwise allow access to the kernel s/turns off/disables/ > + image (eg. setting MSR registers). e.g. > + > + Note, however, that locking down your kernel will prevent some the kernel a kernel > + drivers from functioning because allowing manual configuration of > + hardware parameters is forbidden, lest a device be used to access the > + kernel by DMA. This mostly applies to ISA devices. Is DMA from non-ISA devices OK, or did I miss seeing that patch? > + The kernel lockdown can be triggered by adding lockdown=1 to the > + kernel command line. > diff --git a/security/lock_down.c b/security/lock_down.c > new file mode 100644 > index 000000000000..f35ffdd096ad > --- /dev/null > +++ b/security/lock_down.c > @@ -0,0 +1,65 @@ > +/* Lock down the kernel > + * > + * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved. > + * Written by David Howells (dhowells@xxxxxxxxxx) > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public Licence > + * as published by the Free Software Foundation; either version > + * 2 of the Licence, or (at your option) any later version. fsf.org spells that Licence word as License. :) > + */ -- ~Randy -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html