[V31,09/25] uswsusp: Disable when the kernel is locked down

Message ID	20190326182742.16950-10-matthewgarrett@google.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-security-module-owner@kernel.org> Date: Tue, 26 Mar 2019 11:27:25 -0700 In-Reply-To: <20190326182742.16950-1-matthewgarrett@google.com> Message-Id: <20190326182742.16950-10-matthewgarrett@google.com> Mime-Version: 1.0 References: <20190326182742.16950-1-matthewgarrett@google.com> Subject: [PATCH V31 09/25] uswsusp: Disable when the kernel is locked down From: Matthew Garrett <matthewgarrett@google.com> To: jmorris@namei.org Cc: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, linux-api@vger.kernel.org, luto@kernel.org, Matthew Garrett <mjg59@srcf.ucam.org>, Matthew Garrett <mjg59@google.com>, linux-pm@vger.kernel.org, pavel@ucw.cz, rjw@rjwysocki.net Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk
Series	Add support for kernel lockdown \| expand [V31,00/25] Add support for kernel lockdown [V31,01/25] Add the ability to lock down access to the running kernel image [V31,02/25] Enforce module signatures if the kernel is locked down [V31,03/25] Restrict /dev/{mem,kmem,port} when the kernel is locked down [V31,04/25] kexec_load: Disable at runtime if the kernel is locked down [V31,05/25] Copy secure_boot flag in boot params across kexec reboot [V31,06/25] kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE [V31,07/25] kexec_file: Restrict at runtime if the kernel is locked down [V31,08/25] hibernate: Disable when the kernel is locked down [V31,09/25] uswsusp: Disable when the kernel is locked down [V31,10/25] PCI: Lock down BAR access when the kernel is locked down [V31,11/25] x86: Lock down IO port access when the kernel is locked down [V31,12/25] x86/msr: Restrict MSR access when the kernel is locked down [V31,13/25] ACPI: Limit access to custom_method when the kernel is locked down [V31,14/25] acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down [V31,15/25] acpi: Disable ACPI table override if the kernel is locked down [V31,16/25] Prohibit PCMCIA CIS storage when the kernel is locked down [V31,17/25] Lock down TIOCSSERIAL [V31,18/25] Lock down module params that specify hardware parameters (eg. ioport) [V31,19/25] x86/mmiotrace: Lock down the testmmiotrace module [V31,20/25] Lock down /proc/kcore [V31,21/25] Lock down kprobes when in confidentiality mode [V31,22/25] bpf: Restrict bpf when kernel lockdown is in confidentiality mode [V31,23/25] Lock down perf when in confidentiality mode [V31,24/25] lockdown: Print current->comm in restriction messages [V31,25/25] debugfs: Disable open() when kernel is locked down

Message ID

20190326182742.16950-10-matthewgarrett@google.com (mailing list archive)

State

New, archived

Headers

Date: Tue, 26 Mar 2019 11:27:25 -0700
In-Reply-To: <20190326182742.16950-1-matthewgarrett@google.com>
Message-Id: <20190326182742.16950-10-matthewgarrett@google.com>
Mime-Version: 1.0
References: <20190326182742.16950-1-matthewgarrett@google.com>
Subject: [PATCH V31 09/25] uswsusp: Disable when the kernel is locked down
From: Matthew Garrett <matthewgarrett@google.com>
To: jmorris@namei.org
Cc: linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, dhowells@redhat.com,
        linux-api@vger.kernel.org, luto@kernel.org,
        Matthew Garrett <mjg59@srcf.ucam.org>,
        Matthew Garrett <mjg59@google.com>, linux-pm@vger.kernel.org,
        pavel@ucw.cz, rjw@rjwysocki.net
Content-Type: text/plain; charset="UTF-8"
Sender: owner-linux-security-module@vger.kernel.org
Precedence: bulk

Series

Add support for kernel lockdown | expand

Commit Message

Matthew Garrett March 26, 2019, 6:27 p.m. UTC

From: Matthew Garrett <mjg59@srcf.ucam.org>

uswsusp allows a user process to dump and then restore kernel state, which
makes it possible to modify the running kernel.  Disable this if the kernel
is locked down.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
cc: linux-pm@vger.kernel.org
Cc: pavel@ucw.cz
Cc: rjw@rjwysocki.net
---
 kernel/power/user.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/power/user.c b/kernel/power/user.c
index 2d8b60a3c86b..99e13fd13237 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -52,6 +52,9 @@  static int snapshot_open(struct inode *inode, struct file *filp)
 	if (!hibernation_available())
 		return -EPERM;
 
+	if (kernel_is_locked_down("/dev/snapshot", LOCKDOWN_INTEGRITY))
+		return -EPERM;
+
 	lock_system_sleep();
 
 	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {

[V31,09/25] uswsusp: Disable when the kernel is locked down

Commit Message

Patch