From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5C90C433E0 for ; Thu, 14 Jan 2021 18:36:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B0AEB23B1A for ; Thu, 14 Jan 2021 18:36:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726482AbhANSga (ORCPT ); Thu, 14 Jan 2021 13:36:30 -0500 Received: from aserp2120.oracle.com ([141.146.126.78]:43982 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726367AbhANSg3 (ORCPT ); Thu, 14 Jan 2021 13:36:29 -0500 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 10EIE0dd090600; Thu, 14 Jan 2021 18:35:44 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=content-type : mime-version : subject : from : in-reply-to : date : cc : content-transfer-encoding : message-id : references : to; s=corp-2020-01-29; bh=2kPd0eoKcI0UXs8lpE42ku1jYkaE+GT70viuohVfAbU=; b=wwn28XUWAy6ZeRauPHRNL6wIusSSu33fZk83x4b2bVc73h5Q77JDH+hhtXiTZPxCsU8E oQTGKJXJ4d/6vzxjC7xfoCKoahM0PhnymLpv+h4N7y58HxHl9uZlI4OiACnXGXrX87m5 huxoPvSC+8cSf6jU7129z1k0SHbQ1muJBv+1xphF12jPNGFMRKAyszRUuGvjueYTO0ti E7dJoWz4TO/OKawi2agpm0eapWWrf5VLupseBapbD1auGdp59yNHaMx90j/DCi13TbE4 lR+Qkbs6RRVWCNrsUAEVMj2+t8PKCN5d4A+14nxZS7HEO01jxhFjlri8byEzU0ZuiaNR lA== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by aserp2120.oracle.com with ESMTP id 360kd01mf5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 14 Jan 2021 18:35:44 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 10EIEsho150258; Thu, 14 Jan 2021 18:35:43 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userp3030.oracle.com with ESMTP id 360kenkx2d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 14 Jan 2021 18:35:43 +0000 Received: from abhmp0017.oracle.com (abhmp0017.oracle.com [141.146.116.23]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 10EIZcAQ015580; Thu, 14 Jan 2021 18:35:42 GMT Received: from anon-dhcp-153.1015granger.net (/68.61.232.219) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 14 Jan 2021 10:35:38 -0800 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.4\)) Subject: Re: nfsd vurlerability submit From: Chuck Lever In-Reply-To: Date: Thu, 14 Jan 2021 13:35:37 -0500 Cc: Bruce Fields , Trond Myklebust , Linux NFS Mailing List Content-Transfer-Encoding: quoted-printable Message-Id: <7E14D32D-1B39-4DB1-AE39-B8B34655DC7D@oracle.com> References: <20210108154230.GB950@1wt.eu> <20210111193655.GC2600@fieldses.org> <20210112153208.GF9248@fieldses.org> <8296b696a7fa5591ad3fbb05bfcf6bdf6175cc38.camel@hammerspace.com> <96aea58bde3fe4c09cccd9ead2a1c85eb887d276.camel@hammerspace.com> <74269493859fa65a7f594dadd5d86c74bd910e66.camel@hammerspace.com> <20210114180758.GB3914@fieldses.org> To: Linus Torvalds X-Mailer: Apple Mail (2.3608.120.23.2.4) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9864 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 phishscore=0 spamscore=0 malwarescore=0 suspectscore=0 mlxlogscore=999 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2101140107 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9864 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 phishscore=0 impostorscore=0 bulkscore=0 adultscore=0 suspectscore=0 malwarescore=0 lowpriorityscore=0 clxscore=1011 mlxlogscore=999 mlxscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2101140107 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org > On Jan 14, 2021, at 1:29 PM, Linus Torvalds = wrote: >=20 > On Thu, Jan 14, 2021 at 10:08 AM bfields@fieldses.org > wrote: >>=20 >> I dug around a bit and couldn't find the idea of using filehandle >> guessing plus mountd's following of symlinks to get access to other >> filesystems. That's kind of interesting. >=20 > [ Other people removed from cc, this is just a question about nfsd = cleanliness ] >=20 > I missed if Trond's suggestion to at least fix up ".." to have the > same filehandle as "." for the top export directory was done. If I understand your question correctly... there is a commit in linux-next that simply doesn't return any filehandle for ".." in the root directory. = https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git/commit/?h=3D= for-next&id=3D51b2ee7d006a736a9126e8111d1f24e4fd0afaa6 I intend to send you a PR after a few more days of soak time, unless you'd like me to send it now. -- Chuck Lever