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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 6D13CC433B4 for ; Mon, 12 Apr 2021 16:24:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D63A6135D for ; Mon, 12 Apr 2021 16:24:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244120AbhDLQZL (ORCPT ); Mon, 12 Apr 2021 12:25:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243841AbhDLQYd (ORCPT ); Mon, 12 Apr 2021 12:24:33 -0400 Received: from mail-lf1-x130.google.com (mail-lf1-x130.google.com [IPv6:2a00:1450:4864:20::130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF107C061344 for ; Mon, 12 Apr 2021 09:24:06 -0700 (PDT) Received: by mail-lf1-x130.google.com with SMTP id x13so12234406lfr.2 for ; Mon, 12 Apr 2021 09:24:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ueR+bzUQyBJ6Gmj9fHXIfDenKkhbJd11CuntNjq4ue8=; b=Al2PuI8Jtpzy/NwLxwtBoFYmkJnS/LiklYzPs1W31opZKivVBizLwtQrhvdcCOzNgl iFR4SpalKqJenVbjbDxeUakPBfXOWawua9ad3aoLoJ6u71vmqNsjc2z07HewEM5RCZnE 537Yq4lD1OJ7BIDIr0AJhjMl3v314MH/ZEs9g= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ueR+bzUQyBJ6Gmj9fHXIfDenKkhbJd11CuntNjq4ue8=; b=Kqju2EvoxxyFoCUYuq4d/6DIKbTXVZeWVIgyEzsO9kthqJgi/QecibOoW+qxJac6q5 VoTFUu4nv4XCbsDE0fWT8MrZ21rtE+CZvCdFDkWB9C2F1ZhiXHPB2JO6VZ771SIMTC68 CR3LPWZat9AcS9/BiztFnWoJ3gtrxJqS/Daf0xgGmsQUvq7PhdBRyARFR+Fi9mLoixBf 7HLJzeszR60ue6S9YxXDXvgP5q7O7Lt6oyyuIkYAIhsqqoPa9G/MhBSXWYMwHSDMNF3w FwEjUL9jNHRfKQMzc+2u/RSuDf1+Luqm1pVqvb3h+9Tti2jK1xNfIFpLnO1HgUqFTn19 1DEQ== X-Gm-Message-State: AOAM530LitWMYvC5XtSuJNfnsqW47ks89YEYDXxi04rifKy9V6G5KCVm uWxcntcezEtXdobpYxIv3ICa+UMo9CV31LME X-Google-Smtp-Source: ABdhPJxGYi+/0kYjCplge4+12LQLqMuxdFL1pyh0OU5NX0QS6rkEn8xDOUoI2yqjM23BuvecXWxKvQ== X-Received: by 2002:a05:6512:104e:: with SMTP id c14mr19983844lfb.559.1618244645178; Mon, 12 Apr 2021 09:24:05 -0700 (PDT) Received: from mail-lj1-f169.google.com (mail-lj1-f169.google.com. [209.85.208.169]) by smtp.gmail.com with ESMTPSA id z9sm1111044lfu.138.2021.04.12.09.24.04 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 12 Apr 2021 09:24:04 -0700 (PDT) Received: by mail-lj1-f169.google.com with SMTP id l22so8725595ljc.9 for ; Mon, 12 Apr 2021 09:24:04 -0700 (PDT) X-Received: by 2002:a05:6512:31c7:: with SMTP id j7mr10731751lfe.41.1618244634563; Mon, 12 Apr 2021 09:23:54 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Linus Torvalds Date: Mon, 12 Apr 2021 09:23:38 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v6 24/40] fs: make helpers idmap mount aware To: Anton Altaparmakov Cc: "christian.brauner@ubuntu.com" , "James.Bottomley@hansenpartnership.com" , "adilger.kernel@dilger.ca" , "alban@kinvolk.io" , "arnd@arndb.de" , "casey@schaufler-ca.com" , "containers@lists.linux-foundation.org" , "corbet@lwn.net" , "cyphar@cyphar.com" , "dhowells@redhat.com" , "dmitry.kasatkin@gmail.com" , "ebiederm@xmission.com" , "geofft@ldpreload.com" , "hch@lst.de" , "hirofumi@mail.parknet.co.jp" , "john.johansen@canonical.com" , "josh@joshtriplett.org" , "keescook@chromium.org" , "lennart@poettering.net" , "linux-api@vger.kernel.org" , "linux-ext4@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "linux-integrity@vger.kernel.org" , "linux-security-module@vger.kernel.org" , "linux-xfs@vger.kernel.org" , "luto@kernel.org" , "mpatel@redhat.com" , "paul@paul-moore.com" , "selinux@vger.kernel.org" , "seth.forshee@canonical.com" , "smbarber@chromium.org" , "stephen.smalley.work@gmail.com" , "tkjos@google.com" , "tycho@tycho.ws" , "tytso@mit.edu" , "viro@zeniv.linux.org.uk" , "zohar@linux.ibm.com" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: On Mon, Apr 12, 2021 at 5:05 AM Anton Altaparmakov wrote: > > Shouldn't that be using mnt_userns instead of &init_user_ns both for the setattr_prepare() and setattr_copy() calls? It doesn't matter for a filesystem that hasn't marked itself as supporting idmaps. If the filesystem doesn't set FS_ALLOW_IDMAP, then mnt_userns is always going to be &init_user_ns. That said, I don't think you are wrong - it would probably be a good idea to pass down the 'mnt_userns' argument just to avoid confusion. But if you look at the history, you'll see that adding the mount namespace argument to the helper functions (like setattr_copy()) happened before the actual "switch the filesystem setattr() function over to get the namespace argument". So the current situation is partly an artifact of how the incremental filesystem changes were done. Linus