From patchwork Mon Mar 1 16:15:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 389104 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,DKIMWL_WL_HIGH, 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 A7E2BC433DB for ; Mon, 1 Mar 2021 20:36:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 70B4B601FC for ; Mon, 1 Mar 2021 20:36:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243330AbhCAUft (ORCPT ); Mon, 1 Mar 2021 15:35:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:49676 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243379AbhCAU2Y (ORCPT ); Mon, 1 Mar 2021 15:28:24 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7E0DE65416; Mon, 1 Mar 2021 18:07:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614622047; bh=hxYdr4dB1bXlOK5zIKH2KUT8LQ/NI5Cnto29N8W9ja0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VzyFogSJH2LvIN3dumd/eX/wICSeRMdv5raAA0FJeAOQplnzdnr+iE9cXRc33HHKp ln9ASg+UQ/41MHQoU063cxBgmmt/sbqeHCUfvLx/gfM4Mw29JMdsCsOEakf4NnCwIT h+owEc4F3TqbEzIOKzN4eOOs7G/hBWQLT1yHnGtQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, stable@kernel.org, Chao Yu , Jaegeuk Kim Subject: [PATCH 5.11 738/775] f2fs: enforce the immutable flag on open files Date: Mon, 1 Mar 2021 17:15:06 +0100 Message-Id: <20210301161237.807784811@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161201.679371205@linuxfoundation.org> References: <20210301161201.679371205@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Chao Yu commit e0fcd01510ad025c9bbce704c5c2579294056141 upstream. This patch ports commit 02b016ca7f99 ("ext4: enforce the immutable flag on open files") to f2fs. According to the chattr man page, "a file with the 'i' attribute cannot be modified..." Historically, this was only enforced when the file was opened, per the rest of the description, "... and the file can not be opened in write mode". There is general agreement that we should standardize all file systems to prevent modifications even for files that were opened at the time the immutable flag is set. Eventually, a change to enforce this at the VFS layer should be landing in mainline. Cc: stable@kernel.org Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman --- fs/f2fs/file.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -60,6 +60,9 @@ static vm_fault_t f2fs_vm_page_mkwrite(s bool need_alloc = true; int err = 0; + if (unlikely(IS_IMMUTABLE(inode))) + return VM_FAULT_SIGBUS; + if (unlikely(f2fs_cp_error(sbi))) { err = -EIO; goto err; @@ -870,6 +873,14 @@ int f2fs_setattr(struct dentry *dentry, if (unlikely(f2fs_cp_error(F2FS_I_SB(inode)))) return -EIO; + if (unlikely(IS_IMMUTABLE(inode))) + return -EPERM; + + if (unlikely(IS_APPEND(inode) && + (attr->ia_valid & (ATTR_MODE | ATTR_UID | + ATTR_GID | ATTR_TIMES_SET)))) + return -EPERM; + if ((attr->ia_valid & ATTR_SIZE) && !f2fs_is_compress_backend_ready(inode)) return -EOPNOTSUPP; @@ -4356,6 +4367,11 @@ static ssize_t f2fs_file_write_iter(stru inode_lock(inode); } + if (unlikely(IS_IMMUTABLE(inode))) { + ret = -EPERM; + goto unlock; + } + ret = generic_write_checks(iocb, from); if (ret > 0) { bool preallocated = false; @@ -4420,6 +4436,7 @@ write: if (ret > 0) f2fs_update_iostat(F2FS_I_SB(inode), APP_WRITE_IO, ret); } +unlock: inode_unlock(inode); out: trace_f2fs_file_write_iter(inode, iocb->ki_pos,