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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,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 ACE81C04ABB for ; Thu, 13 Sep 2018 13:56:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 71FC4204FD for ; Thu, 13 Sep 2018 13:56:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 71FC4204FD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731398AbeIMTGK (ORCPT ); Thu, 13 Sep 2018 15:06:10 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:34180 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730563AbeIMTGK (ORCPT ); Thu, 13 Sep 2018 15:06:10 -0400 Received: from localhost (ip-213-127-77-73.ip.prioritytelecom.net [213.127.77.73]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id F18B2D10; Thu, 13 Sep 2018 13:56:32 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chao Yu , Jaegeuk Kim , Sasha Levin Subject: [PATCH 4.18 089/197] f2fs: fix avoid race between truncate and background GC Date: Thu, 13 Sep 2018 15:30:38 +0200 Message-Id: <20180913131845.090273910@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20180913131841.568116777@linuxfoundation.org> References: <20180913131841.568116777@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chao Yu [ Upstream commit a33c150237a20d97a174243bc658c86502f9d370 ] Thread A Background GC - f2fs_setattr isize to 0 - truncate_setsize - gc_data_segment - f2fs_get_read_data_page page #0 - set_page_dirty - set_cold_data - f2fs_truncate - f2fs_setattr isize to 4k - read 4k <--- hit data in cached page #0 Above race condition can cause read out invalid data in a truncated page, fix it by i_gc_rwsem[WRITE] lock. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/f2fs/data.c | 4 ++++ fs/f2fs/file.c | 37 +++++++++++++++++++++++-------------- 2 files changed, 27 insertions(+), 14 deletions(-) --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2149,8 +2149,12 @@ static void f2fs_write_failed(struct add if (to > i_size) { down_write(&F2FS_I(inode)->i_mmap_sem); + down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); + truncate_pagecache(inode, i_size); f2fs_truncate_blocks(inode, i_size, true); + + up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); up_write(&F2FS_I(inode)->i_mmap_sem); } } --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -782,22 +782,26 @@ int f2fs_setattr(struct dentry *dentry, } if (attr->ia_valid & ATTR_SIZE) { - if (attr->ia_size <= i_size_read(inode)) { - down_write(&F2FS_I(inode)->i_mmap_sem); - truncate_setsize(inode, attr->ia_size); + bool to_smaller = (attr->ia_size <= i_size_read(inode)); + + down_write(&F2FS_I(inode)->i_mmap_sem); + down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); + + truncate_setsize(inode, attr->ia_size); + + if (to_smaller) err = f2fs_truncate(inode); - up_write(&F2FS_I(inode)->i_mmap_sem); - if (err) - return err; - } else { - /* - * do not trim all blocks after i_size if target size is - * larger than i_size. - */ - down_write(&F2FS_I(inode)->i_mmap_sem); - truncate_setsize(inode, attr->ia_size); - up_write(&F2FS_I(inode)->i_mmap_sem); + /* + * do not trim all blocks after i_size if target size is + * larger than i_size. + */ + up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); + up_write(&F2FS_I(inode)->i_mmap_sem); + + if (err) + return err; + if (!to_smaller) { /* should convert inline inode here */ if (!f2fs_may_inline_data(inode)) { err = f2fs_convert_inline_inode(inode); @@ -944,13 +948,18 @@ static int punch_hole(struct inode *inod blk_start = (loff_t)pg_start << PAGE_SHIFT; blk_end = (loff_t)pg_end << PAGE_SHIFT; + down_write(&F2FS_I(inode)->i_mmap_sem); + down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); + truncate_inode_pages_range(mapping, blk_start, blk_end - 1); f2fs_lock_op(sbi); ret = f2fs_truncate_hole(inode, pg_start, pg_end); f2fs_unlock_op(sbi); + + up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); up_write(&F2FS_I(inode)->i_mmap_sem); } }