From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:46312 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2403901AbeHATEB (ORCPT ); Wed, 1 Aug 2018 15:04:01 -0400 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 4.14 061/246] f2fs: fix race in between GC and atomic open Date: Wed, 1 Aug 2018 18:49:31 +0200 Message-Id: <20180801165014.623520730@linuxfoundation.org> In-Reply-To: <20180801165011.700991984@linuxfoundation.org> References: <20180801165011.700991984@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chao Yu [ Upstream commit 27319ba4044c0c67d62ae39e53c0118c89f0a029 ] Thread GC thread - f2fs_ioc_start_atomic_write - get_dirty_pages - filemap_write_and_wait_range - f2fs_gc - do_garbage_collect - gc_data_segment - move_data_page - f2fs_is_atomic_file - set_page_dirty - set_inode_flag(, FI_ATOMIC_FILE) Dirty data page can still be generated by GC in race condition as above call stack. This patch adds fi->dio_rwsem[WRITE] in f2fs_ioc_start_atomic_write to avoid such race. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/f2fs/file.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1630,6 +1630,8 @@ static int f2fs_ioc_start_atomic_write(s inode_lock(inode); + down_write(&F2FS_I(inode)->dio_rwsem[WRITE]); + if (f2fs_is_atomic_file(inode)) goto out; @@ -1659,6 +1661,7 @@ inc_stat: stat_inc_atomic_write(inode); stat_update_max_atomic_write(inode); out: + up_write(&F2FS_I(inode)->dio_rwsem[WRITE]); inode_unlock(inode); mnt_drop_write_file(filp); return ret;