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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F352DECAAD5 for ; Mon, 12 Sep 2022 15:39:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229877AbiILPjq (ORCPT ); Mon, 12 Sep 2022 11:39:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40114 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229953AbiILPjn (ORCPT ); Mon, 12 Sep 2022 11:39:43 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 64D0A6397 for ; Mon, 12 Sep 2022 08:39:42 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 27C29B80DB9 for ; Mon, 12 Sep 2022 15:39:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C3513C433C1; Mon, 12 Sep 2022 15:39:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1662997179; bh=MOdzIQtvwZrIZeYWgAorj/0pcEr85t2z2V/ng6h3GaM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nzQ4GL23rZMxIiI2gcwNbRbd8TvZRoW1fHAwN/x4hHh127TrVyb5+RssRnmHnwBpG MmpeAOpBWaBK0YhOmVELUzWgEztt13h6zaBzvEGquyKEUHO7PTk7dRI1/J2nQi+1dP sHANhxec5hrC9+XYAQPdEnwUtQoVHLPkC2kEGsJSXna3i3TxMlD8Z4/jEncU8BLyHn 2i2CX+okl7DKNkR7HqiXphjPsAUDTjPTzc8m2D0xwnPODkZhm/I0Soui+xqgHy888f q6yrjozRZ9Fj9KKnewiYADQGgaJboafdNDDq5kw5+2aAkt2k+Rs+rl1IWK9/vBiF2e 5S8vMTZRCGT3g== Date: Mon, 12 Sep 2022 08:39:38 -0700 From: Jaegeuk Kim To: Chao Yu Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Chao Yu Subject: Re: [PATCH v2] f2fs: fix to disallow getting inner inode via f2fs_iget() Message-ID: References: <20220830225358.300027-1-chao@kernel.org> <0af788ed-8797-22a2-ae0c-433fdd6a2188@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/08, Chao Yu wrote: > On 2022/9/8 10:19, Jaegeuk Kim wrote: > > On 09/08, Chao Yu wrote: > > > On 2022/9/8 10:02, Jaegeuk Kim wrote: > > > > On 08/31, Chao Yu wrote: > > > > > From: Chao Yu > > > > > > > > > > Introduce f2fs_iget_inner() for f2fs_fill_super() to get inner inode: > > > > > meta inode, node inode or compressed inode, and add f2fs_check_nid_range() > > > > > in f2fs_iget() to avoid getting inner inode from external interfaces. > > > > > > > > So, we don't want to check the range of inner inode numbers? What'd be the > > > > way to check it's okay? > > > > > > For node_ino, meta_ino, root_ino, we have checked them in sanity_check_raw_super() > > > as below: > > > > > > /* check reserved ino info */ > > > if (le32_to_cpu(raw_super->node_ino) != 1 || > > > le32_to_cpu(raw_super->meta_ino) != 2 || > > > le32_to_cpu(raw_super->root_ino) != 3) { > > > f2fs_info(sbi, "Invalid Fs Meta Ino: node(%u) meta(%u) root(%u)", > > > le32_to_cpu(raw_super->node_ino), > > > le32_to_cpu(raw_super->meta_ino), > > > le32_to_cpu(raw_super->root_ino)); > > > return -EFSCORRUPTED; > > > } > > > > > > compressed_ino should always be NM_I(sbi)->max_nid, it can be checked in > > > f2fs_init_compress_inode()? > > > > Hmm, I'm not sure whether we really need this patch, since it'd look better > > to handle all the iget with single f2fs_iget? > > Well, the main concern is previously f2fs_iget() won't check validation for inner > inode due to it will skip do_read_inode() - f2fs_check_nid_range(), so that in a > fuzzed image, caller may pass inner ino into f2fs_iget(), result in incorrect use > of inner inode. So I add f2fs_check_nid_range() in prior to f2fs_iget_inner() in > f2fs_iget() as below to detect and avoid this case. FWIW, sanity_check_raw_super() checked the inode numbers. > > > > > > +struct inode *f2fs_iget(struct super_block *sb, unsigned long ino) > > > > > +{ > > > > > + int ret; > > > > > + > > > > > + ret = f2fs_check_nid_range(F2FS_SB(sb), ino); > > > > > + if (ret) > > > > > + return ERR_PTR(ret); > > > > > + > > > > > + return f2fs_iget_inner(sb, ino);