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=-7.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,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 C3EEEC433DB for ; Mon, 22 Feb 2021 10:48:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 72E1C64E40 for ; Mon, 22 Feb 2021 10:48:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230400AbhBVKrk (ORCPT ); Mon, 22 Feb 2021 05:47:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230384AbhBVKre (ORCPT ); Mon, 22 Feb 2021 05:47:34 -0500 Received: from mail-il1-x134.google.com (mail-il1-x134.google.com [IPv6:2607:f8b0:4864:20::134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2EC58C06178C; Mon, 22 Feb 2021 02:46:32 -0800 (PST) Received: by mail-il1-x134.google.com with SMTP id z18so10338453ile.9; Mon, 22 Feb 2021 02:46:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=FHZQdAl+UcOWFEKhnz51zgke6JFt0Apq4o1l3JnjKAI=; b=BR+j5tJ76HJ/MrYsYUrbRAckIqs5GbHwJGeClmEn6L96g5exlOi5QZeYy7ZvvUq4wG JynsiK3Ygr53wwHj/6xTghe+kBd/tlpV+84eFX7WAr43T3wJM6RxORvPN/SWBOQcmm/V OoKN52LfbVvqCkqFMVdKThs3kIt7ud25jOtaGGi27pwzkLMpfZkfWDMXhO/0XWVxeHNW YNFiJrC+vbItmaQ0DB6DrpAZa5DxlS9iPabxEwCvsI56Fg7CXnHrPIstiiguxxU8trtS UEN2f5vaSNWxCzmhs+clpU2Tne/l4pqXV4nSiWT8T5wYJUusloUdhy2E0X1FJyMMETi5 rX9w== 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=FHZQdAl+UcOWFEKhnz51zgke6JFt0Apq4o1l3JnjKAI=; b=LNh4N6sPXV7BizilQviZVG0NxTW+YGvAJV56Vmc0n2Qmf+D47Sz4Imy41Bx3U22brU Bpl5BGl/NNBkGnm+626cTlJB4Kn8ea1J6ostS1O1Cs0Yjaz7O2B1ywdoDiKobLU69W0e 3ZUjwZeNnmAn5HxgESxxpu7knlOvjtthAQshTNDankoWYZlleUhA2De7HiTh9YnqUw/I ZrHjfucI1Q84k2DwMzL6UuxMiMe2hbdXtDViBC2jWJAXylBbJrm6WdXf5H3K/8d5Hpz1 NxwFuwbbJKWD5FTVlPewX6hT/+fMY9+BQ8KnRszKTZHvnceMexIYwcrjPz1yFTXDcYXF PUAw== X-Gm-Message-State: AOAM531mRTTUAgIKBv3SEBJK95koZ2d+cnLrM9y2TxzdDnsN+a6GF8v9 qOOTK3/8v7cdNjnQOW5uKwxAMYc8AKYJl6TNSa0= X-Google-Smtp-Source: ABdhPJwCt22ShOeNCpiOnTx3JXmkEO2/x+8xvzSi9yrlR8q5F2qEMQngv4H4MSPX9tkAXc2eNDJvntVrkaQKi+YyX+Y= X-Received: by 2002:a92:740c:: with SMTP id p12mr1161730ilc.9.1613990791635; Mon, 22 Feb 2021 02:46:31 -0800 (PST) MIME-Version: 1.0 References: <20210221195833.23828-1-lhenriques@suse.de> <20210222102456.6692-1-lhenriques@suse.de> In-Reply-To: <20210222102456.6692-1-lhenriques@suse.de> From: Amir Goldstein Date: Mon, 22 Feb 2021 12:46:20 +0200 Message-ID: Subject: Re: [PATCH v8] vfs: fix copy_file_range regression in cross-fs copies To: Luis Henriques Cc: Jeff Layton , Steve French , Miklos Szeredi , Trond Myklebust , Anna Schumaker , Alexander Viro , "Darrick J. Wong" , Dave Chinner , Greg KH , Nicolas Boichat , Ian Lance Taylor , Luis Lozano , Andreas Dilger , Olga Kornievskaia , Christoph Hellwig , ceph-devel , linux-kernel , CIFS , samba-technical , linux-fsdevel , Linux NFS Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Mon, Feb 22, 2021 at 12:23 PM Luis Henriques wrote: > > A regression has been reported by Nicolas Boichat, found while using the > copy_file_range syscall to copy a tracefs file. Before commit > 5dae222a5ff0 ("vfs: allow copy_file_range to copy across devices") the > kernel would return -EXDEV to userspace when trying to copy a file across > different filesystems. After this commit, the syscall doesn't fail anymore > and instead returns zero (zero bytes copied), as this file's content is > generated on-the-fly and thus reports a size of zero. > > This patch restores some cross-filesystem copy restrictions that existed > prior to commit 5dae222a5ff0 ("vfs: allow copy_file_range to copy across > devices"). Filesystems are still allowed to fall-back to the VFS > generic_copy_file_range() implementation, but that has now to be done > explicitly. > > nfsd is also modified to fall-back into generic_copy_file_range() in case > vfs_copy_file_range() fails with -EOPNOTSUPP or -EXDEV. > > Fixes: 5dae222a5ff0 ("vfs: allow copy_file_range to copy across devices") > Link: https://lore.kernel.org/linux-fsdevel/20210212044405.4120619-1-drinkcat@chromium.org/ > Link: https://lore.kernel.org/linux-fsdevel/CANMq1KDZuxir2LM5jOTm0xx+BnvW=ZmpsG47CyHFJwnw7zSX6Q@mail.gmail.com/ > Link: https://lore.kernel.org/linux-fsdevel/20210126135012.1.If45b7cdc3ff707bc1efa17f5366057d60603c45f@changeid/ > Reported-by: Nicolas Boichat > Signed-off-by: Luis Henriques > --- Reviewed-by: Amir Goldstein Thanks, Amir.