| From | Matthew Garrett <> | Subject | [PATCH 09/12] uswsusp: Disable when securelevel is set | Date | Mon, 9 Sep 2013 11:49:43 -0400 |
| |
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> --- kernel/power/user.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/kernel/power/user.c b/kernel/power/user.c index 4ed81e7..520a9c4 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> @@ -48,6 +49,9 @@ static int snapshot_open(struct inode *inode, struct file *filp) struct snapshot_data *data; int error; + if (get_securelevel() > 0) + return -EPERM; + lock_system_sleep(); if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { -- 1.8.3.1
|