From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: [PATCH 09/12] uswsusp: Disable when trusted_kernel is true Date: Wed, 26 Feb 2014 15:11:10 -0500 Message-ID: <1393445473-15068-10-git-send-email-matthew.garrett@nebula.com> References: <1393445473-15068-1-git-send-email-matthew.garrett@nebula.com> Return-path: In-Reply-To: <1393445473-15068-1-git-send-email-matthew.garrett-05XSO3Yj/JvQT0dZR+AlfA@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, jmorris-gx6/JNMH7DfYtjvyW6yDsg@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Matthew Garrett List-Id: linux-efi@vger.kernel.org uswsusp allows a user process to dump and then restore kernel state, which makes it possible to modify the running kernel. Disable this if trusted_kernel is true. Signed-off-by: Matthew Garrett --- kernel/power/user.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/power/user.c b/kernel/power/user.c index 98d3575..2d7a5d3 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -24,6 +24,7 @@ #include #include #include +#include #include @@ -49,6 +50,9 @@ static int snapshot_open(struct inode *inode, struct file *filp) struct snapshot_data *data; int error; + if (get_trusted_kernel()) + return -EPERM; + lock_system_sleep(); if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { -- 1.8.5.3