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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 52579C433ED for ; Tue, 6 Apr 2021 12:03:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B46161019 for ; Tue, 6 Apr 2021 12:03:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343674AbhDFMDj (ORCPT ); Tue, 6 Apr 2021 08:03:39 -0400 Received: from sender2-op-o12.zoho.com.cn ([163.53.93.243]:17130 "EHLO sender2-op-o12.zoho.com.cn" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235453AbhDFMDh (ORCPT ); Tue, 6 Apr 2021 08:03:37 -0400 ARC-Seal: i=1; a=rsa-sha256; t=1617710601; cv=none; d=zoho.com.cn; s=zohoarc; b=bjYUYrJ0iVhNnYKjAH26Z8VnlTsieB08hOF7mXEjVsMynLmx0R8iuJHjXoY0bpMDoL3XjfnczKC33pn5mj3AH+6ZRv8Qi1qWMM53kahbPOBYSlwf4PVboxQp4JY5N5YD4fLEdqMgWORi43RmPzIc2yNGy60kfSUoW3DR361sSyc= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com.cn; s=zohoarc; t=1617710601; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:To; bh=q95V60AvGuzYowYrxHiFurC3fUSXBpkBq0I9BwPz9O0=; b=ljw+MdvSHh4J+borhkZtGCTfio8tHi3sGRCQxH8Baypmvgo7RbAHKV9DLaTpwlaZSd/MR8rn+C7zq3PuIcKwIiH0JuvKqDGjsLobtSp2/XL0Cv6PooO6RiMepUzs+hr3UDR1NhJ5YcH75tjGEaNh1XLjgjDQIY72FyyKzbj50F8= ARC-Authentication-Results: i=1; mx.zoho.com.cn; dkim=pass header.i=mykernel.net; spf=pass smtp.mailfrom=cgxu519@mykernel.net; dmarc=pass header.from= header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1617710601; s=zohomail; d=mykernel.net; i=cgxu519@mykernel.net; h=From:To:Cc:Message-ID:Subject:Date:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Content-Type; bh=q95V60AvGuzYowYrxHiFurC3fUSXBpkBq0I9BwPz9O0=; b=HHQInbAaE1xVFMOStGy+6EQ81xT1dlrN7RsrSczXX/qTJ1ayLmKBsxiESDtq6UIf L0CtI0GK9lwACtePMP5UlX9tweNvJ5ah00UfHgOLZkE1k53uFwL67WU+mRy+qVPvRpR XrB40Vp+OPdpyq67jG4iWjKnz+DmkkaWvamyVasw= Received: from localhost.localdomain (159.75.42.226 [159.75.42.226]) by mx.zoho.com.cn with SMTPS id 1617710600498586.6069236070001; Tue, 6 Apr 2021 20:03:20 +0800 (CST) From: Chengguang Xu To: miklos@szeredi.hu Cc: linux-unionfs@vger.kernel.org, Chengguang Xu Message-ID: <20210406120245.1338326-2-cgxu519@mykernel.net> Subject: [PATCH v2 2/3] ovl: check actual copy-up size Date: Tue, 6 Apr 2021 20:02:44 +0800 X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210406120245.1338326-1-cgxu519@mykernel.net> References: <20210406120245.1338326-1-cgxu519@mykernel.net> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoCNMailClient: External Content-Type: text/plain; charset=utf8 Precedence: bulk List-ID: X-Mailing-List: linux-unionfs@vger.kernel.org In order to simplify truncate operation on the file which only has lower, we allow specifying larger size than lower file when calling ovl_copy_up_data(), so we should check actual copy size carefully before doing copy-up. Signed-off-by: Chengguang Xu --- fs/overlayfs/copy_up.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 8b92b3ba3c46..a1a9a150405a 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -156,6 +156,9 @@ static int ovl_copy_up_data(struct ovl_fs *ofs, struct = path *old, =09=09goto out_fput; =09} =20 +=09len =3D (len <=3D i_size_read(file_inode(old_file))) ? len : +=09=09=09=09i_size_read(file_inode(old_file)); + =09/* Try to use clone_file_range to clone up within the same fs */ =09cloned =3D do_clone_file_range(old_file, 0, new_file, 0, len, 0); =09if (cloned =3D=3D len) --=20 2.27.0