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 9E971C54EE9 for ; Tue, 13 Sep 2022 06:44:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230491AbiIMGoh (ORCPT ); Tue, 13 Sep 2022 02:44:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230196AbiIMGod (ORCPT ); Tue, 13 Sep 2022 02:44:33 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B20DB6174 for ; Mon, 12 Sep 2022 23:44:31 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 4F48261325 for ; Tue, 13 Sep 2022 06:44:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 47F0EC433C1; Tue, 13 Sep 2022 06:44:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1663051470; bh=0e9xHpDVUmc8i3sNd336+sReKkmZIVLIQ0HMJ/k2lbw=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=S5aRUfxdIXYuJPeMRwCwwVPHQdoxY1IV8PHIqccGRdOwJL6B2XCOLzW+tV5+ZUNhX jaLVJc1Jlm8nvDc7LMLNBptPTB9aWLLZVLVxOPucOlJFKbFgVkMeJH3Pq9Sm9ibYhk 0wWiHBPlTdZO5XxwSb75tRyEuupHghBGAP9hNfy4NllflSuSAASYI1dfs3NSa4DlE5 KBydAI+DCRa+XdH7KmTW87CSwVhVRQj+B8t2YPc5aFuXWdtQ35EJFuUmHo7hmvvKbq vxqJgcD3PXQjUQN9hTP8CjwsHqDMprGa2hLnaedMnAwlaHLtPyJpkXGGzekjUGhxEB JJVdyLyk+UAFA== Message-ID: <4efaecb4-7179-ae6c-05b6-49a168b3c8bd@kernel.org> Date: Tue, 13 Sep 2022 14:44:24 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH v2] f2fs: fix to disallow getting inner inode via f2fs_iget() Content-Language: en-US To: Jaegeuk Kim Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org References: <20220830225358.300027-1-chao@kernel.org> <0af788ed-8797-22a2-ae0c-433fdd6a2188@kernel.org> <6c54e0b1-9c75-af90-565b-61174ddb5cbc@kernel.org> From: Chao Yu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/9/13 13:54, Jaegeuk Kim wrote: > On 09/13, Chao Yu wrote: >> On 2022/9/12 23:39, Jaegeuk Kim wrote: >>> 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. >> >> However, previously, f2fs_iget() will return inner inode to caller directly, if caller >> passes meta_ino, node_ino or compress_ino to f2fs_iget()? > > Do you want to do sanity check on corrupted dentry? If so, how about checking Yes, including: - corrupted ino in dentry - corrupted ino of orphan inode As I replied in this thread: https://lore.kernel.org/lkml/b1c74dc1-8d01-9041-9469-036273c5618d@kernel.org/ > it in f2fs_iget instead? > > if (is_meta_ino(ino)) { > if (!(inode->i_state & I_NEW) > return -EFSCORRUPTED; > goto make_now; > } Fine to me, let me revise in v3. Thanks, > >> >> Thanks, >> >>> >>>> >>>>>>>> +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);