diff mbox series

[V33,11/30] uswsusp: Disable when the kernel is locked down

Message ID 20190621011941.186255-12-matthewgarrett@google.com (mailing list archive)
State Not Applicable, archived
Headers show
Series None | expand

Commit Message

Matthew Garrett June 21, 2019, 1:19 a.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 | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/kernel/power/user.c b/kernel/power/user.c
index 2d8b60a3c86b..8a8d7f1c8fbb 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -24,6 +24,7 @@ 
 #include <linux/console.h>
 #include <linux/cpu.h>
 #include <linux/freezer.h>
+#include <linux/security.h>
 
 #include <linux/uaccess.h>
 
@@ -52,6 +53,9 @@  static int snapshot_open(struct inode *inode, struct file *filp)
 	if (!hibernation_available())
 		return -EPERM;
 
+	if (security_is_locked_down(LOCKDOWN_HIBERNATION))
+		return -EPERM;
+
 	lock_system_sleep();
 
 	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {