[PATCH 11/24] uswsusp: Disable when the kernel is locked down
From: David Howells
Date: Wed Apr 05 2017 - 13:12:28 EST
From: Matthew Garrett <mjg59@xxxxxxxxxxxxx>
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: Matthew Garrett <mjg59@xxxxxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---
kernel/power/user.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 22df9f7ff672..e4b926d329b7 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())
+ return -EPERM;
+
lock_system_sleep();
if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {