[PATCH V3 09/11] uswsusp: Disable when module loading is restricted

From: Matthew Garrett
Date: Tue Sep 03 2013 - 19:51:08 EST


uswsusp allows a user process to dump and then restore kernel state, which
makes it possible to avoid module loading restrictions. Prevent this when
any restrictions have been imposed on loading modules.

Signed-off-by: Matthew Garrett <matthew.garrett@xxxxxxxxxx>
---
kernel/power/user.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/kernel/power/user.c b/kernel/power/user.c
index 4ed81e7..15cb72f 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/module.h>

#include <asm/uaccess.h>

@@ -48,6 +49,9 @@ static int snapshot_open(struct inode *inode, struct file *filp)
struct snapshot_data *data;
int error;

+ if (secure_modules())
+ return -EPERM;
+
lock_system_sleep();

if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
--
1.8.3.1

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