From patchwork Wed Dec 2 15:40:09 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Seth Forshee X-Patchwork-Id: 7747951 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id F35D29F387 for ; Wed, 2 Dec 2015 15:46:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3118A204E0 for ; Wed, 2 Dec 2015 15:46:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2C44620520 for ; Wed, 2 Dec 2015 15:46:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932856AbbLBPqw (ORCPT ); Wed, 2 Dec 2015 10:46:52 -0500 Received: from mail-ig0-f172.google.com ([209.85.213.172]:34988 "EHLO mail-ig0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932835AbbLBPmY (ORCPT ); Wed, 2 Dec 2015 10:42:24 -0500 Received: by igl9 with SMTP id 9so113069928igl.0 for ; Wed, 02 Dec 2015 07:42:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=F6DHgWVc3nkRbgh1dVw6jfQtAywZIA/MSQXS2nxBBFE=; b=abqtq8M29gVLNtaTCwUPmuRCwDbwzdfmjt6reDcbSkBtUVeySSsOski71jE0AfVYAG 27cg/tc0pUEJR5cZCLfwxa3F9dH1oPoTcNR2fl6ZPx9C45IGMI/wU4kSK3yD7qc1nJSO 4Txa2Z4FyoybSmuzpcT/aXmY9AaXkUlI+VFRtP9bgDJE8fnmlDZ2iJUQPKEW8+sN6o0r 52U+Syf70AQqPhHRjx8o0CVE+RFnikBIVJ9eNyBkGIERv8HSWQ4g28jhaciorzqEnqCO 2fD15hkwVEQH6+iauxvZBJMXR+Es8fzqxJPgtDeciU0Umi9D8TWiw//qw43sIpED/7Wz jnKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=F6DHgWVc3nkRbgh1dVw6jfQtAywZIA/MSQXS2nxBBFE=; b=lk0Sw52jmXQv3R5gdBfbqnlg6AqQj6HJ6otlXohpMCrzcsOf+nU2Hm/Y4JGFcP0QBw +4+qhvkbLYDd28HZMbYsfGcE033Ynksk/HSdUWp9W0M60FdmJATljQobyPut965OZzMj yTyMrmKwi3fXRXgqq2CgQRNg+3OM+Cycm05xrSQkjhzbt7FtBA5q+1r7Y3v0actnNoQj FFnuJWYKNxY5Vc+Zc2FlzsNOnALVesCMO1G9vFvM7SgB3FDOmchMTl++k4oeTh+2qASi SRbDrINRjBQyBBfa24yHzc7wJ6Kn8s/nTnpXlBEbYs3hCmOQ4oxw8H2TCPigNgef59mA 1sIw== X-Gm-Message-State: ALoCoQm8xVxdD3uEC7Fld5JHLxMkuEibfilZ7UomYEnwZaqtsAWZ45BZ3Ay3PrVl8JsUNDphN80e X-Received: by 10.50.20.138 with SMTP id n10mr4511143ige.11.1449070943981; Wed, 02 Dec 2015 07:42:23 -0800 (PST) Received: from localhost (199-87-125-144.dyn.kc.surewest.net. [199.87.125.144]) by smtp.gmail.com with ESMTPSA id vs11sm11487427igb.6.2015.12.02.07.42.23 (version=TLS1_2 cipher=AES128-SHA bits=128/128); Wed, 02 Dec 2015 07:42:23 -0800 (PST) From: Seth Forshee To: "Eric W. Biederman" , Alexander Viro Cc: Serge Hallyn , Richard Weinberger , Austin S Hemmelgarn , Miklos Szeredi , linux-bcache@vger.kernel.org, dm-devel@redhat.com, linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, linux-fsdevel@vger.kernel.org, fuse-devel@lists.sourceforge.net, linux-security-module@vger.kernel.org, selinux@tycho.nsa.gov, Seth Forshee Subject: [PATCH 09/19] fs: Refuse uid/gid changes which don't map into s_user_ns Date: Wed, 2 Dec 2015 09:40:09 -0600 Message-Id: <1449070821-73820-10-git-send-email-seth.forshee@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1449070821-73820-1-git-send-email-seth.forshee@canonical.com> References: <1449070821-73820-1-git-send-email-seth.forshee@canonical.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID,T_RP_MATCHES_RCVD,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add checks to inode_change_ok to verify that uid and gid changes will map into the superblock's user namespace. If they do not fail with -EOVERFLOW. This cannot be overriden with ATTR_FORCE. Signed-off-by: Seth Forshee Acked-by: Serge Hallyn --- fs/attr.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/fs/attr.c b/fs/attr.c index 6530ced19697..55b46e3aa888 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -42,6 +42,17 @@ int inode_change_ok(const struct inode *inode, struct iattr *attr) return error; } + /* + * Verify that uid/gid changes are valid in the target namespace + * of the superblock. This cannot be overriden using ATTR_FORCE. + */ + if (ia_valid & ATTR_UID && + from_kuid(inode->i_sb->s_user_ns, attr->ia_uid) == (uid_t)-1) + return -EOVERFLOW; + if (ia_valid & ATTR_GID && + from_kgid(inode->i_sb->s_user_ns, attr->ia_gid) == (gid_t)-1) + return -EOVERFLOW; + /* If force is set do it anyway. */ if (ia_valid & ATTR_FORCE) return 0;