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=-14.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,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 01AF5C43466 for ; Mon, 21 Sep 2020 16:45:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BE22D23998 for ; Mon, 21 Sep 2020 16:45:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600706716; bh=UlDZOmMEl82BvN+q3X8IemklTtPmKk+JfenhcMngvX4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RT6haDuDcNfBqE5L5zHAPYD4YCWam0J+X1RMH2s9rE0bA8y7VbuRzZi21fK+k3k7U DZrMSoj+6iCJJmz2QsconcdfEzTxSzG71IPscAcD7Rc0khWf3r3GuDKqDqEoiaY/tw AtgKOtZhQZOLC5pBgDuq6iA4oFbNt+5/dikibQvw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726818AbgIUQpP (ORCPT ); Mon, 21 Sep 2020 12:45:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:50866 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729045AbgIUQpH (ORCPT ); Mon, 21 Sep 2020 12:45:07 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 18EF323998; Mon, 21 Sep 2020 16:45:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600706706; bh=UlDZOmMEl82BvN+q3X8IemklTtPmKk+JfenhcMngvX4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fZhWaH+lRecwH7VM4ozS/sMVupSS5ipyYWO3e+2ZdD/GuoxevaLkvM8/Q113Q/zuY Ggoh9icaBKeY43etG1mbcTgcQRmQllLHaMYNiflfn+1cbXTnvEMd7Y1WrRIEZHYHfc cZPIBQQII9qbaDqjHSdkEhyHbB/MVarN1QA0Ri5Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gabriel Krisman Bertazi , Chao Yu , Jaegeuk Kim , Sasha Levin Subject: [PATCH 5.8 031/118] f2fs: Return EOF on unaligned end of file DIO read Date: Mon, 21 Sep 2020 18:27:23 +0200 Message-Id: <20200921162037.757914751@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200921162036.324813383@linuxfoundation.org> References: <20200921162036.324813383@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Gabriel Krisman Bertazi [ Upstream commit 20d0a107fb35f37578b919f62bd474d6d358d579 ] Reading past end of file returns EOF for aligned reads but -EINVAL for unaligned reads on f2fs. While documentation is not strict about this corner case, most filesystem returns EOF on this case, like iomap filesystems. This patch consolidates the behavior for f2fs, by making it return EOF(0). it can be verified by a read loop on a file that does a partial read before EOF (A file that doesn't end at an aligned address). The following code fails on an unaligned file on f2fs, but not on btrfs, ext4, and xfs. while (done < total) { ssize_t delta = pread(fd, buf + done, total - done, off + done); if (!delta) break; ... } It is arguable whether filesystems should actually return EOF or -EINVAL, but since iomap filesystems support it, and so does the original DIO code, it seems reasonable to consolidate on that. Signed-off-by: Gabriel Krisman Bertazi Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/data.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 6e9017e6a8197..403e8033c974b 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -3463,6 +3463,9 @@ static int check_direct_IO(struct inode *inode, struct iov_iter *iter, unsigned long align = offset | iov_iter_alignment(iter); struct block_device *bdev = inode->i_sb->s_bdev; + if (iov_iter_rw(iter) == READ && offset >= i_size_read(inode)) + return 1; + if (align & blocksize_mask) { if (bdev) blkbits = blksize_bits(bdev_logical_block_size(bdev)); -- 2.25.1