diff mbox series

[V33,10/30] hibernate: Disable when the kernel is locked down

Message ID 20190621011941.186255-11-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: Josh Boyer <jwboyer@fedoraproject.org>

There is currently no way to verify the resume image when returning
from hibernate.  This might compromise the signed modules trust model,
so until we can work with signed hibernate images we disable it when the
kernel is locked down.

Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Cc: rjw@rjwysocki.net
Cc: pavel@ucw.cz
cc: linux-pm@vger.kernel.org
---
 include/linux/security.h     | 1 +
 kernel/power/hibernate.c     | 4 +++-
 security/lockdown/lockdown.c | 1 +
 3 files changed, 5 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/include/linux/security.h b/include/linux/security.h
index 2d3c69b9fd04..deac722f0d86 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -85,6 +85,7 @@  enum lockdown_reason {
 	LOCKDOWN_MODULE_SIGNATURE,
 	LOCKDOWN_DEV_MEM,
 	LOCKDOWN_KEXEC,
+	LOCKDOWN_HIBERNATION,
 	LOCKDOWN_INTEGRITY_MAX,
 	LOCKDOWN_CONFIDENTIALITY_MAX,
 };
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index abef759de7c8..5804ffeb8622 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -32,6 +32,7 @@ 
 #include <linux/ctype.h>
 #include <linux/genhd.h>
 #include <linux/ktime.h>
+#include <linux/security.h>
 #include <trace/events/power.h>
 
 #include "power.h"
@@ -70,7 +71,8 @@  static const struct platform_hibernation_ops *hibernation_ops;
 
 bool hibernation_available(void)
 {
-	return (nohibernate == 0);
+	return nohibernate == 0 &&
+		!security_is_locked_down(LOCKDOWN_HIBERNATION);
 }
 
 /**
diff --git a/security/lockdown/lockdown.c b/security/lockdown/lockdown.c
index 94af1c3583d8..42b7bc467ef6 100644
--- a/security/lockdown/lockdown.c
+++ b/security/lockdown/lockdown.c
@@ -21,6 +21,7 @@  static char *lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1] = {
 	[LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading",
 	[LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port",
 	[LOCKDOWN_KEXEC] = "kexec of unsigned images",
+	[LOCKDOWN_HIBERNATION] = "hibernation",
 	[LOCKDOWN_INTEGRITY_MAX] = "integrity",
 	[LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
 };