From: Matthew Garrett <matthew.garrett@nebula.com>
Date: Mon, 9 Sep 2013 22:49:43 +0000 (-0700)
Subject: uswsusp: Disable when securelevel is set
X-Git-Tag: v4.1.12-92~310^2~6
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=eb4fa31a4a8f9d5974dc518edb2c5044926a0b61;p=users%2Fjedix%2Flinux-maple.git

uswsusp: Disable when securelevel is set

Orabug: 21539498

uswsusp allows a user process to dump and then restore kernel state, which
makes it possible to modify the running kernel. Disable this if securelevel
has been set.

Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
---

diff --git a/kernel/power/user.c b/kernel/power/user.c
index 526e8911460a0..40618bf41620a 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 <asm/uaccess.h>
 
@@ -52,6 +53,9 @@ static int snapshot_open(struct inode *inode, struct file *filp)
 	if (!hibernation_available())
 		return -EPERM;
 
+	if (get_securelevel() > 0)
+		return -EPERM;
+
 	lock_system_sleep();
 
 	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {