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=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 ABA6BC433E0 for ; Wed, 12 Aug 2020 01:35:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8B26B20678 for ; Wed, 12 Aug 2020 01:35:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597196129; bh=XRaUsfOfArlLCj6aQQTjDLCujMRU5oNoOzT3ATLhLIA=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=j2ow7vU7soq5dE6rg1aiqLbYQ249K+KBSnz9QRMtF9Tk13iMb8tKe5NCuCgf6K3qJ EJd5CTRPMXtJ9BCnZqo7jEvJ9M/ff78zPqfHMWk2dmhwRyijUwHY0CVGf0WoeI7s36 ZSx/I9395xlDPAIh6+F8Wv9WvsBkcAAM5msoLk4E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726483AbgHLBf3 (ORCPT ); Tue, 11 Aug 2020 21:35:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:36438 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726430AbgHLBf3 (ORCPT ); Tue, 11 Aug 2020 21:35:29 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 437DC20658; Wed, 12 Aug 2020 01:35:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597196128; bh=XRaUsfOfArlLCj6aQQTjDLCujMRU5oNoOzT3ATLhLIA=; h=Date:From:To:Subject:In-Reply-To:From; b=RnZjaG5VRX1vT7BFV68Dk5/ldXtxSTX6Gf2cXZ7Ri/2dubG8EQq8L/RntlIrUAHjU LrogpH3/xpx9zb3Kcc4DBEKJfnf8zcNoqzxBi2zwllRC3ZziI1Bsv1eYUFNfcQ7zkE cknEXJ9zwBIxhDG8V4VM0x14WZ20aV9mm3VEn1/4= Date: Tue, 11 Aug 2020 18:35:27 -0700 From: Andrew Morton To: akpm@linux-foundation.org, anenbupt@gmail.com, ebiggers@google.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, stable@vger.kernel.org, torvalds@linux-foundation.org, viro@zeniv.linux.org.uk Subject: [patch 099/165] fs/minix: don't allow getting deleted inodes Message-ID: <20200812013527.F8o9sw3XQ%akpm@linux-foundation.org> In-Reply-To: <20200811182949.e12ae9a472e3b5e27e16ad6c@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: mm-commits-owner@vger.kernel.org Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Eric Biggers Subject: fs/minix: don't allow getting deleted inodes If an inode has no links, we need to mark it bad rather than allowing it to be accessed. This avoids WARNINGs in inc_nlink() and drop_nlink() when doing directory operations on a fuzzed filesystem. Link: http://lkml.kernel.org/r/20200628060846.682158-3-ebiggers@kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+a9ac3de1b5de5fb10efc@syzkaller.appspotmail.com Reported-by: syzbot+df958cf5688a96ad3287@syzkaller.appspotmail.com Signed-off-by: Eric Biggers Cc: Alexander Viro Cc: Qiujun Huang Cc: Signed-off-by: Andrew Morton --- fs/minix/inode.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) --- a/fs/minix/inode.c~fs-minix-dont-allow-getting-deleted-inodes +++ a/fs/minix/inode.c @@ -468,6 +468,13 @@ static struct inode *V1_minix_iget(struc iget_failed(inode); return ERR_PTR(-EIO); } + if (raw_inode->i_nlinks == 0) { + printk("MINIX-fs: deleted inode referenced: %lu\n", + inode->i_ino); + brelse(bh); + iget_failed(inode); + return ERR_PTR(-ESTALE); + } inode->i_mode = raw_inode->i_mode; i_uid_write(inode, raw_inode->i_uid); i_gid_write(inode, raw_inode->i_gid); @@ -501,6 +508,13 @@ static struct inode *V2_minix_iget(struc iget_failed(inode); return ERR_PTR(-EIO); } + if (raw_inode->i_nlinks == 0) { + printk("MINIX-fs: deleted inode referenced: %lu\n", + inode->i_ino); + brelse(bh); + iget_failed(inode); + return ERR_PTR(-ESTALE); + } inode->i_mode = raw_inode->i_mode; i_uid_write(inode, raw_inode->i_uid); i_gid_write(inode, raw_inode->i_gid); _