From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753519AbdJSOxt (ORCPT ); Thu, 19 Oct 2017 10:53:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56994 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753491AbdJSOxq (ORCPT ); Thu, 19 Oct 2017 10:53:46 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 7DB07B64D Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=dhowells@redhat.com Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 25/27] Lock down /proc/kcore From: David Howells To: linux-security-module@vger.kernel.org Cc: gnomes@lxorguk.ukuu.org.uk, linux-efi@vger.kernel.org, matthew.garrett@nebula.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, jforbes@redhat.com Date: Thu, 19 Oct 2017 15:53:42 +0100 Message-ID: <150842482228.7923.9630520914833154257.stgit@warthog.procyon.org.uk> In-Reply-To: <150842463163.7923.11081723749106843698.stgit@warthog.procyon.org.uk> References: <150842463163.7923.11081723749106843698.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Thu, 19 Oct 2017 14:53:46 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Disallow access to /proc/kcore when the kernel is locked down to prevent access to cryptographic data. Signed-off-by: David Howells --- fs/proc/kcore.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index 45629f4b5402..176cf749e650 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -549,6 +549,8 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos) static int open_kcore(struct inode *inode, struct file *filp) { + if (kernel_is_locked_down("/proc/kcore")) + return -EPERM; if (!capable(CAP_SYS_RAWIO)) return -EPERM;