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=-3.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 6C1B7C56201 for ; Thu, 29 Oct 2020 00:19:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0199720780 for ; Thu, 29 Oct 2020 00:19:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="e3DmSyyf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389211AbgJ1Wo6 (ORCPT ); Wed, 28 Oct 2020 18:44:58 -0400 Received: from mout.gmx.net ([212.227.15.18]:47667 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731064AbgJ1WmD (ORCPT ); Wed, 28 Oct 2020 18:42:03 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1603924922; bh=mjjgd5ywvv3HNXkKe5faSF1dHJHIMuYeEx9hiIOdEh8=; h=X-UI-Sender-Class:From:To:Cc:Subject:References:Date:In-Reply-To; b=e3DmSyyfBc+guSAyIs3YUwc4qrLsWdo0YGyopaPjPoKjoqAkAd9jYzhPAmbXvFGdq rtetInYKpNEUgmhGf23EIdzfH9qjwy/JqXYPE39KPmzKMajEKY3ZNfnAs0fyAK7ajP ilWeYo8UmeYpivnPR3sY/tODDi0qawhtpHtVZL28= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from localhost.localdomain ([79.223.32.86]) by mail.gmx.com (mrgmx005 [212.227.17.190]) with ESMTPSA (Nemesis) id 1N0XCw-1kCrOG1TYi-00wUJi; Wed, 28 Oct 2020 19:30:24 +0100 Received: by localhost.localdomain (Postfix, from userid 1000) id 62417800D8; Wed, 28 Oct 2020 19:30:23 +0100 (CET) From: Sven Joachim To: Masahiro Yamada Cc: Linux Kbuild mailing list , Michal Marek , Linux Kernel Mailing List , Guillem Jover Subject: Re: [PATCH 1/2] builddeb: Fix rootless build in setuid/setgid directory References: <20201026193217.402412-1-svenjoac@gmx.de> Date: Wed, 28 Oct 2020 19:30:23 +0100 In-Reply-To: (Masahiro Yamada's message of "Wed, 28 Oct 2020 15:00:22 +0900") Message-ID: <871rhi19vk.fsf@turtle.gmx.de> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Provags-ID: V03:K1:Yl6/pxi4e/xbPe4GCfZUCwKzrh9fZJX/GZ2OIKcQmsACydYSDYf aiRC2bhxwZXaQU63FPIBSDo3opoaFHI+qABi60moHMy601HTzDG6yFF5Yc/LPP970XALYwN jBOI4bQsvE0eccEhLt7vcbYkKoMGix8cnBIF+joWEDDwCeW9gcOWx/+nNcgi/l88YZkgmHv q33yhyfq4s2ZPFQtZCk2A== X-UI-Out-Filterresults: notjunk:1;V03:K0:R5fUqhJ/1WM=:hDagFnQG+3Zv/jY8bJJbBk mBI8lx4FAf+68qBKu+FGehObFPZkrgpPRJNFzFKTExJGn8Gws8xOCy0rnPMIQF0uDS2um5PEK 9mRUM5QSuEAOVuos8Ur1ENNIdUf+is8A7ZUx0WYKP0fAR16BB8Uc4WEQGzQBouKDmoarVxRRx sGUTC/WqyAqpo0eEn4+rpaexGYa9SwI2UshFSSydy7cYYVAQEGzlk+DoB98ENvR3r1/DUi0e8 aEGTU6GswOdTGRWCPIOrjYTGr+L8Kbol0ukoV5MniMvwA1hKyHyXpNttzGuL1JqGgFiNs/TqS Zt3F6nsGrVfmLvlPEXQJVGko63h2RW7KjFJXZn61/A8XcKZPWtpWPKRU4ow03ceiR9WV7yorN /FfBdnfeQhbNyYMK56t1b4C9Piz+XAh8Yw1p3MVR3fB+HthVxH7wF66j5xlXwtVUATz+y3S6k /R7DVMmpEbipMjJZbTnrHwlYxO08aRyW48LxEKp0d12jDNiIuSnbDSTezOV0qoCKL45SiMoSj KFpPO1oWdnawYgHg1etVL3ivl96m07rWMUHc/EUS4xV6VyElFNeSMt9iYIBZimJh9La+LUcED wi0ym2ny7f++T1hs8Gr3/TqU2O/R39BXtNy+akxiAQ1uHsaE2fa/A4H8GIjHiYyhTkPPgk020 mhh5R1WT8PAklObbk92jUaasq/bf5J8dBLYKHm0yvc1ZSJleu3VPjSgn4auIulbGsPXFPTpYP bNauEFeBcAMYWZCsi7Lg3FIGU7hVjUOGkf9oaq+V67IJvNQwj0ErhSQ0P4aNrl9JLhaESfNQq Lgmf50eC7IpCL92wR+Sg1NJ/ty8x8UH2bc0d2Gfq4a9HxcYPS2OGNaqWHy4gIWnv+7Z5mb/lV cxrfFW1fZSxJ4jv5tFjw== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-10-28 15:00 +0900, Masahiro Yamada wrote: > On Tue, Oct 27, 2020 at 4:32 AM Sven Joachim wrote: >> >> Building 5.10-rc1 in a setgid directory failed with the following >> error: >> >> dpkg-deb: error: control directory has bad permissions 2755 (must be >> >=0755 and <=0775) >> >> When building with fakeroot, the earlier chown call would have removed >> the setgid bits, but in a rootless build they remain. >> > > > Applied to linux-kbuild. Thanks. I don't see it there, have you pushed it out yet? > I agreed with "g-s" but was not sure about "u-s" > because nothing is explained about setuid, > and the setuid bit against directories seems to have no effect. > > > > > > It was interesting to read this article: > https://superuser.com/questions/471844/why-is-setuid-ignored-on-directories > > > > Also, it is summarized in the wikipedia > https://en.wikipedia.org/wiki/Setuid#setuid_and_setgid_on_directories > > "The setuid permission set on a directory is ignored on most UNIX and > Linux systems.[citation needed] However FreeBSD can be configured to > interpret setuid in a manner similar to setgid, in which case it > forces all files and sub-directories created in a directory to be > owned by that directory's owner - a simple form of inheritance.[5] > This is generally not needed on most systems derived from BSD, since > by default directories are treated as if their setgid bit is always > set, regardless of the actual value. As is stated in open(2), "When a > new file is created it is given the group of the directory which > contains it."" > > > After all, I am convinced that it would not hurt to do "u-s" > although I have never tested kernel builds on FreeBSD. Agreed, setuid directories should not end up in the .deb files even if that bit does currently nothing. Cheers, Sven