From: David Howells <dhowells@redhat.com>
To: torvalds@linux-foundation.org
Cc: linux-man@vger.kernel.org, linux-api@vger.kernel.org,
jmorris@namei.org, linux-kernel@vger.kernel.org,
dhowells@redhat.com, linux-security-module@vger.kernel.org
Subject: [PATCH 00/24] security: Add kernel lockdown
Date: Wed, 11 Apr 2018 17:24:39 +0100 [thread overview]
Message-ID: <152346387861.4030.4408662483445703127.stgit@warthog.procyon.org.uk> (raw)
Hi Linus,
I've modified my lockdown mode patches to remove the EFI/secure-boot
interaction and to ignore kexec. Would you be willing to accept this?
David
---
Here's a set of patches to institute a "locked-down mode" in the kernel.
If enabled, the lockdown can be triggered either by configuration (in which
case it cannot be lifted) or by command line (lockdown=1). In the latter
case, there's an option to allow it to be lifted by a SysRq key on an
attached keyboard.
Three config options are provided:
(1) CONFIG_LOCK_DOWN_KERNEL makes lockdown mode available.
(2) CONFIG_LOCK_DOWN_MANDATORY builds the kernel with lockdown mode
enabled at compile time and removes the ability to disable it.
(3) CONFIG_ALLOW_LOCKDOWN_LIFT_BY_SYSRQ will allow a SysRq combination to
lift the lockdown. On x86 this is SysRq+x. The keys must be pressed
on an attached keyboard. Echoing into the trigger file won't work.
Inside the kernel, kernel_is_locked_down() is used to check if the kernel
is in lockdown mode.
For the moment, there is only one mode that locks everything down. Andy
would prefer that there be two modes, one of which allows the kernel to be
read, but not modified and the other which allows neither. Modifying this
later to allow what Andy wants wouldn't be particularly hard as there isn't
much additional functionality that this would enable (ie. /dev/kmem,
/dev/kcore, bpf and perf).
A manual page, kernel_lockdown.7, is proposed, to which people will be
directed by messages in dmesg. This lists the features that are restricted
amongst other things.
The patches are tagged here:
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
tags/lockdown-20180410
The patches can be found here also:
http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=lockdown
---
David Howells (11):
Add the ability to lock down access to the running kernel image
Enforce module signatures if the kernel is locked down
Prohibit PCMCIA CIS storage when the kernel is locked down
Lock down TIOCSSERIAL
Lock down module params that specify hardware parameters (eg. ioport)
x86/mmiotrace: Lock down the testmmiotrace module
Lock down /proc/kcore
Lock down kprobes
bpf: Restrict kernel image access functions when the kernel is locked down
Lock down perf
debugfs: Restrict debugfs when the kernel is locked down
Josh Boyer (2):
hibernate: Disable when the kernel is locked down
acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
Kyle McMartin (1):
Add a SysRq option to lift kernel lockdown
Linn Crosetto (2):
acpi: Disable ACPI table override if the kernel is locked down
acpi: Disable APEI error injection if the kernel is locked down
Matthew Garrett (7):
Restrict /dev/{mem,kmem,port} when the kernel is locked down
kexec_load: Disable at runtime if the kernel is locked down
uswsusp: Disable when the kernel is locked down
PCI: Lock down BAR access when the kernel is locked down
x86: Lock down IO port access when the kernel is locked down
x86/msr: Restrict MSR access when the kernel is locked down
ACPI: Limit access to custom_method when the kernel is locked down
Mimi Zohar (1):
ima: require secure_boot rules in lockdown mode
arch/x86/include/asm/setup.h | 2 +
arch/x86/kernel/ioport.c | 6 +-
arch/x86/kernel/msr.c | 10 +++
arch/x86/kernel/setup.c | 2 +
arch/x86/mm/testmmiotrace.c | 3 +
drivers/acpi/apei/einj.c | 3 +
drivers/acpi/custom_method.c | 3 +
drivers/acpi/osl.c | 2 -
drivers/acpi/tables.c | 5 ++
drivers/char/mem.c | 2 +
drivers/input/misc/uinput.c | 1
drivers/pci/pci-sysfs.c | 9 +++
drivers/pci/proc.c | 9 +++
drivers/pci/syscall.c | 3 +
drivers/pcmcia/cistpl.c | 3 +
drivers/tty/serial/serial_core.c | 6 ++
drivers/tty/sysrq.c | 19 ++++--
fs/debugfs/file.c | 28 +++++++++
fs/debugfs/inode.c | 30 +++++++++
fs/proc/kcore.c | 2 +
include/linux/input.h | 5 ++
include/linux/kernel.h | 32 ++++++++++
include/linux/sysrq.h | 8 ++-
kernel/bpf/syscall.c | 3 +
kernel/debug/kdb/kdb_main.c | 2 -
kernel/events/core.c | 5 ++
kernel/kexec.c | 7 ++
kernel/kprobes.c | 3 +
kernel/module.c | 56 +++++++++++++-----
kernel/params.c | 26 +++++++-
kernel/power/hibernate.c | 2 -
kernel/power/user.c | 3 +
security/Kconfig | 34 ++++++++++-
security/Makefile | 3 +
security/integrity/ima/ima_policy.c | 39 +++++++++---
security/lock_down.c | 112 +++++++++++++++++++++++++++++++++++
36 files changed, 443 insertions(+), 45 deletions(-)
create mode 100644 security/lock_down.c
next reply other threads:[~2018-04-11 16:24 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-11 16:24 David Howells [this message]
2018-04-11 16:24 ` [PATCH 01/24] Add the ability to lock down access to the running kernel image David Howells
2018-04-11 16:44 ` Jann Horn
2018-04-11 17:37 ` Randy Dunlap
2018-04-11 18:50 ` Miguel Ojeda
2018-04-11 19:56 ` Greg KH
2018-04-11 17:49 ` David Howells
2018-04-11 18:09 ` Linus Torvalds
2018-04-11 18:35 ` Justin Forbes
2018-04-11 21:05 ` Jordan Glover
2018-04-11 22:38 ` Linus Torvalds
2018-04-12 13:09 ` Justin Forbes
2018-04-12 16:52 ` Linus Torvalds
2018-04-12 2:57 ` Andy Lutomirski
2018-04-11 16:24 ` [PATCH 02/24] Add a SysRq option to lift kernel lockdown David Howells
2018-04-11 17:05 ` Jann Horn
2018-04-13 20:22 ` Pavel Machek
2018-04-11 16:24 ` [PATCH 03/24] ima: require secure_boot rules in lockdown mode David Howells
2018-04-11 16:25 ` [PATCH 04/24] Enforce module signatures if the kernel is locked down David Howells
2018-04-11 16:25 ` [PATCH 05/24] Restrict /dev/{mem, kmem, port} when " David Howells
2018-04-11 16:25 ` [PATCH 06/24] kexec_load: Disable at runtime if " David Howells
2018-04-11 19:00 ` Eric W. Biederman
2018-04-11 20:09 ` Mimi Zohar
2018-04-12 11:38 ` Mimi Zohar
2018-04-11 20:05 ` David Howells
2018-04-11 16:25 ` [PATCH 07/24] hibernate: Disable when " David Howells
2018-04-13 20:22 ` Pavel Machek
2018-04-19 14:38 ` David Howells
2018-04-22 14:34 ` Andy Lutomirski
2018-04-26 7:26 ` Pavel Machek
2018-04-26 7:34 ` Rafael J. Wysocki
2018-04-26 8:20 ` Jiri Kosina
2018-05-23 8:46 ` joeyli
2018-04-11 16:25 ` [PATCH 08/24] uswsusp: " David Howells
2018-04-11 16:25 ` [PATCH 09/24] PCI: Lock down BAR access " David Howells
2018-04-11 16:25 ` [PATCH 10/24] x86: Lock down IO port " David Howells
2018-04-11 16:25 ` [PATCH 11/24] x86/msr: Restrict MSR " David Howells
2018-04-11 16:25 ` [PATCH 12/24] ACPI: Limit access to custom_method " David Howells
2018-04-11 16:26 ` [PATCH 13/24] acpi: Ignore acpi_rsdp kernel param when the kernel has been " David Howells
2018-04-11 16:26 ` [PATCH 14/24] acpi: Disable ACPI table override if the kernel is " David Howells
2018-04-11 16:26 ` [PATCH 15/24] acpi: Disable APEI error injection " David Howells
2018-04-11 16:26 ` [PATCH 16/24] Prohibit PCMCIA CIS storage when " David Howells
2018-04-11 16:26 ` [PATCH 17/24] Lock down TIOCSSERIAL David Howells
2018-04-11 16:26 ` [PATCH 18/24] Lock down module params that specify hardware parameters (eg. ioport) David Howells
2018-04-11 17:22 ` Randy Dunlap
2018-04-11 16:26 ` [PATCH 19/24] x86/mmiotrace: Lock down the testmmiotrace module David Howells
2018-04-11 16:26 ` [PATCH 20/24] Lock down /proc/kcore David Howells
2018-04-11 16:26 ` [PATCH 21/24] Lock down kprobes David Howells
2018-04-11 16:27 ` [PATCH 22/24] bpf: Restrict kernel image access functions when the kernel is locked down David Howells
2018-04-11 16:27 ` [PATCH 23/24] Lock down perf David Howells
2018-04-11 16:27 ` [PATCH 24/24] debugfs: Restrict debugfs when the kernel is locked down David Howells
2018-04-11 17:26 ` Randy Dunlap
2018-04-11 18:50 ` Eric W. Biederman
2018-04-11 19:54 ` Greg KH
2018-04-11 20:08 ` David Howells
2018-04-11 20:09 ` David Howells
2018-04-11 20:33 ` Greg KH
2018-04-12 2:54 ` Andy Lutomirski
2018-04-12 8:23 ` Greg KH
2018-04-12 14:19 ` Andy Lutomirski
2018-04-13 20:22 ` Pavel Machek
2018-04-19 14:35 ` David Howells
2018-05-10 11:01 ` Pavel Machek
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