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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 37A53C433FF for ; Tue, 6 Aug 2019 00:42:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 02146214C6 for ; Tue, 6 Aug 2019 00:42:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565052139; bh=eZwQBDcR/MKYEfWG81eygG4AefN+C5bI0r2OySbuQH0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=OnqHF/NPIdjXMC2MwbLKEGFLjRPX1jbapcCLBrpEAPcB3BPFlif0cuSVGm4xWXWif a/o5J7mrGRP+26AFpUfG6K0cUemxGTNJbvmZ/09xQgWi+0CfqwsxZwPrtmBFUALCFs 4K0ugUwW9FLh6xcxCJVYCxiarSlwhn6rzug7r8t0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731117AbfHFAmR (ORCPT ); Mon, 5 Aug 2019 20:42:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:56666 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728483AbfHFAmR (ORCPT ); Mon, 5 Aug 2019 20:42:17 -0400 Received: from localhost (unknown [104.132.0.81]) (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 6F09D2147A; Tue, 6 Aug 2019 00:42:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565052136; bh=eZwQBDcR/MKYEfWG81eygG4AefN+C5bI0r2OySbuQH0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hZTdUh7m+TxBSmTs1N9DcHxM8FaEQOdounaDItLqslNEzK+yF2IKj+bbhmz8mgVMJ /dN79jv0RBiOXWzAmzAamqFYi8tzCE66mk+DmHzlpQtB2jFWpFcM16V4/wIJgzwdLx v/S0twBm+UcvLi7A5PnuHNeL+2s37gvWfMf3XW58= Date: Mon, 5 Aug 2019 17:42:15 -0700 From: Jaegeuk Kim To: Chao Yu Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, chao@kernel.org Subject: Re: [PATCH] Revert "f2fs: avoid out-of-range memory access" Message-ID: <20190806004215.GC98101@jaegeuk-macbookpro.roam.corp.google.com> References: <20190802101548.96543-1-yuchao0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190802101548.96543-1-yuchao0@huawei.com> User-Agent: Mutt/1.8.2 (2017-04-18) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/02, Chao Yu wrote: > As Pavel Machek reported: > > "We normally use -EUCLEAN to signal filesystem corruption. Plus, it is > good idea to report it to the syslog and mark filesystem as "needing > fsck" if filesystem can do that." > > Still we need improve the original patch with: > - use unlikely keyword > - add message print > - return EUCLEAN > > However, after rethink this patch, I don't think we should add such > condition check here as below reasons: > - We have already checked the field in f2fs_sanity_check_ckpt(), > - If there is fs corrupt or security vulnerability, there is nothing > to guarantee the field is integrated after the check, unless we do > the check before each of its use, however no filesystem does that. > - We only have similar check for bitmap, which was added due to there > is bitmap corruption happened on f2fs' runtime in product. > - There are so many key fields in SB/CP/NAT did have such check > after f2fs_sanity_check_{sb,cp,..}. > > So I propose to revert this unneeded check. IIRC, this came from security vulnerability report which can access out-of-boundary memory region. Could you write another patch to address the above issues? > > This reverts commit 56f3ce675103e3fb9e631cfb4131fc768bc23e9a. > > Signed-off-by: Chao Yu > --- > fs/f2fs/segment.c | 5 ----- > 1 file changed, 5 deletions(-) > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index 9693fa4c8971..2eff9c008ae0 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -3492,11 +3492,6 @@ static int read_compacted_summaries(struct f2fs_sb_info *sbi) > seg_i = CURSEG_I(sbi, i); > segno = le32_to_cpu(ckpt->cur_data_segno[i]); > blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]); > - if (blk_off > ENTRIES_IN_SUM) { > - f2fs_bug_on(sbi, 1); > - f2fs_put_page(page, 1); > - return -EFAULT; > - } > seg_i->next_segno = segno; > reset_curseg(sbi, i, 0); > seg_i->alloc_type = ckpt->alloc_type[i]; > -- > 2.18.0.rc1