From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992907AbbEOXPK (ORCPT ); Fri, 15 May 2015 19:15:10 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:43343 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992868AbbEOXPE (ORCPT ); Fri, 15 May 2015 19:15:04 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Windisch , "Eric W. Biederman" Subject: [PATCH 4.0 10/60] mnt: Fix fs_fully_visible to verify the root directory is visible Date: Fri, 15 May 2015 16:14:11 -0700 Message-Id: <20150515231019.137075605@linuxfoundation.org> X-Mailer: git-send-email 2.4.0 In-Reply-To: <20150515231018.815421141@linuxfoundation.org> References: <20150515231018.815421141@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Eric W. Biederman" commit 7e96c1b0e0f495c5a7450dc4aa7c9a24ba4305bd upstream. This fixes a dumb bug in fs_fully_visible that allows proc or sys to be mounted if there is a bind mount of part of /proc/ or /sys/ visible. Reported-by: Eric Windisch Signed-off-by: "Eric W. Biederman" Signed-off-by: Greg Kroah-Hartman --- fs/namespace.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/fs/namespace.c +++ b/fs/namespace.c @@ -3178,6 +3178,12 @@ bool fs_fully_visible(struct file_system if (mnt->mnt.mnt_sb->s_type != type) continue; + /* This mount is not fully visible if it's root directory + * is not the root directory of the filesystem. + */ + if (mnt->mnt.mnt_root != mnt->mnt.mnt_sb->s_root) + continue; + /* This mount is not fully visible if there are any child mounts * that cover anything except for empty directories. */