Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755151Ab3IIPya (ORCPT ); Mon, 9 Sep 2013 11:54:30 -0400 Received: from cavan.codon.org.uk ([93.93.128.6]:44986 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754615Ab3IIPwO (ORCPT ); Mon, 9 Sep 2013 11:52:14 -0400 From: Matthew Garrett To: linux-kernel@vger.kernel.org Cc: keescook@chromium.org, gregkh@linuxfoundation.org, hpa@zytor.com, linux-efi@vger.kernel.org, jmorris@namei.org, linux-security-module@vger.kernel.org, Matthew Garrett Subject: [PATCH 09/12] uswsusp: Disable when securelevel is set Date: Mon, 9 Sep 2013 11:49:43 -0400 Message-Id: <1378741786-18430-10-git-send-email-matthew.garrett@nebula.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1378741786-18430-1-git-send-email-matthew.garrett@nebula.com> References: <1378741786-18430-1-git-send-email-matthew.garrett@nebula.com> X-SA-Do-Not-Run: Yes X-SA-Exim-Connect-IP: 2001:470:1f07:1371:5d52:9ee3:3e84:6668 X-SA-Exim-Mail-From: matthew.garrett@nebula.com X-SA-Exim-Scanned: No (on cavan.codon.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1111 Lines: 39 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 --- 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 #include #include +#include #include @@ -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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/