From patchwork Tue Jan 26 06:32:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chandan Babu R X-Patchwork-Id: 12047735 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 656CBC433E0 for ; Tue, 26 Jan 2021 18:34:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3948A2224C for ; Tue, 26 Jan 2021 18:34:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727242AbhAZRYW (ORCPT ); Tue, 26 Jan 2021 12:24:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731797AbhAZGde (ORCPT ); Tue, 26 Jan 2021 01:33:34 -0500 Received: from mail-pj1-x1032.google.com (mail-pj1-x1032.google.com [IPv6:2607:f8b0:4864:20::1032]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3C89C06174A for ; Mon, 25 Jan 2021 22:32:53 -0800 (PST) Received: by mail-pj1-x1032.google.com with SMTP id md11so1446386pjb.0 for ; Mon, 25 Jan 2021 22:32:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=UajVql0+fX8/PSAE042XQ9DAknMby2LMCreHtOKK9j0=; b=jwZ9LfJ5Qx5zSwpFyjJ8TkgajQI5J6bwVL1O05CbIkrINuOTw5dKdmKLxORZA9dO4D 4jPJ5uLQ+Dgka8WN/6FzP9RIf0ftYs6I/nAKg9Aju8lC3G9gjPmRsnqPbNuwiif9ttGA ojq9P2uJr/lr8RNATi+efUvxghAqjfi2faXL2S5cJyBPGKLWIedpqq9sff29Gh/DwLo4 2rNhuQX1OWTr4TvW4/4ruaaT9MqSChW9rbcx6CSDXX1Jg0G8tO9OYdQDDYEZ41JR2Vx+ v0J4DjSHyrpj62JfINOOx1X0tfeIykzM4lpPfy/bIkE1kR3ZsmQhiut8MxST8NrYSU3K zCcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=UajVql0+fX8/PSAE042XQ9DAknMby2LMCreHtOKK9j0=; b=QEpodtubdfXG8ouLllKZOtOLhpeYxwGdG+29emeqA88KCP5XbigfKexFF7irxuAhOH C3ve5SGl0h10Se39OV/A4GzCzzLsvCESSvtJg4VGfWOkN1DCI8NJfpaPGpk1VQkUTRVw 9vjYrCNznEuX0avvqjYj1YsfTNQyk2NLc9wwQMXSzNVastZLHmh/sry+91rUikUwZ9EV CA77E6EGzS2SCdcXDwls9p+SEh59IuS2rEhZuvCg2dOP1rNPfPv7SW9LeLzFOski4a5y PRgfnn6aCxhaJVbhItd+iLP2bywjOomE4vBc6hTKPiOl9F2djXgNaG/7vr0j/Ja82/fs dCig== X-Gm-Message-State: AOAM530LCDbWAqaLFzFicEzb/OLenzYgCA+P4cPYncsRPaWibCMcdaSg dSaadXtwbXLjfv0SDJXAUf9B/PD2Cw0= X-Google-Smtp-Source: ABdhPJwmn6kUmozSDoXDuPFzwdos5fkKIiQ+7BFG2azq7Aivnb/ZrxS0kqCDHXzdFI4kn82RoNGPJQ== X-Received: by 2002:a17:90a:da01:: with SMTP id e1mr4416358pjv.58.1611642773326; Mon, 25 Jan 2021 22:32:53 -0800 (PST) Received: from localhost.localdomain ([122.167.33.191]) by smtp.gmail.com with ESMTPSA id w21sm17296578pff.220.2021.01.25.22.32.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Jan 2021 22:32:52 -0800 (PST) From: Chandan Babu R To: linux-xfs@vger.kernel.org Cc: Chandan Babu R , djwong@kernel.org, hch@lst.de, allison.henderson@oracle.com, "Darrick J . Wong" Subject: [PATCH V15 01/16] xfs: Add helper for checking per-inode extent count overflow Date: Tue, 26 Jan 2021 12:02:17 +0530 Message-Id: <20210126063232.3648053-2-chandanrlinux@gmail.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210126063232.3648053-1-chandanrlinux@gmail.com> References: <20210126063232.3648053-1-chandanrlinux@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org XFS does not check for possible overflow of per-inode extent counter fields when adding extents to either data or attr fork. For e.g. 1. Insert 5 million xattrs (each having a value size of 255 bytes) and then delete 50% of them in an alternating manner. 2. On a 4k block sized XFS filesystem instance, the above causes 98511 extents to be created in the attr fork of the inode. xfsaild/loop0 2008 [003] 1475.127209: probe:xfs_inode_to_disk: (ffffffffa43fb6b0) if_nextents=98511 i_ino=131 3. The incore inode fork extent counter is a signed 32-bit quantity. However the on-disk extent counter is an unsigned 16-bit quantity and hence cannot hold 98511 extents. 4. The following incorrect value is stored in the attr extent counter, # xfs_db -f -c 'inode 131' -c 'print core.naextents' /dev/loop0 core.naextents = -32561 This commit adds a new helper function (i.e. xfs_iext_count_may_overflow()) to check for overflow of the per-inode data and xattr extent counters. Future patches will use this function to make sure that an FS operation won't cause the extent counter to overflow. Suggested-by: Darrick J. Wong Reviewed-by: Allison Henderson Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Chandan Babu R --- fs/xfs/libxfs/xfs_inode_fork.c | 23 +++++++++++++++++++++++ fs/xfs/libxfs/xfs_inode_fork.h | 2 ++ 2 files changed, 25 insertions(+) diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c index 7575de5cecb1..8d48716547e5 100644 --- a/fs/xfs/libxfs/xfs_inode_fork.c +++ b/fs/xfs/libxfs/xfs_inode_fork.c @@ -23,6 +23,7 @@ #include "xfs_da_btree.h" #include "xfs_dir2_priv.h" #include "xfs_attr_leaf.h" +#include "xfs_types.h" kmem_zone_t *xfs_ifork_zone; @@ -728,3 +729,25 @@ xfs_ifork_verify_local_attr( return 0; } + +int +xfs_iext_count_may_overflow( + struct xfs_inode *ip, + int whichfork, + int nr_to_add) +{ + struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork); + uint64_t max_exts; + uint64_t nr_exts; + + if (whichfork == XFS_COW_FORK) + return 0; + + max_exts = (whichfork == XFS_ATTR_FORK) ? MAXAEXTNUM : MAXEXTNUM; + + nr_exts = ifp->if_nextents + nr_to_add; + if (nr_exts < ifp->if_nextents || nr_exts > max_exts) + return -EFBIG; + + return 0; +} diff --git a/fs/xfs/libxfs/xfs_inode_fork.h b/fs/xfs/libxfs/xfs_inode_fork.h index a4953e95c4f3..0beb8e2a00be 100644 --- a/fs/xfs/libxfs/xfs_inode_fork.h +++ b/fs/xfs/libxfs/xfs_inode_fork.h @@ -172,5 +172,7 @@ extern void xfs_ifork_init_cow(struct xfs_inode *ip); int xfs_ifork_verify_local_data(struct xfs_inode *ip); int xfs_ifork_verify_local_attr(struct xfs_inode *ip); +int xfs_iext_count_may_overflow(struct xfs_inode *ip, int whichfork, + int nr_to_add); #endif /* __XFS_INODE_FORK_H__ */