From patchwork Wed Jun 1 10:45:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amir Goldstein X-Patchwork-Id: 12866678 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 66E40C433EF for ; Wed, 1 Jun 2022 10:46:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352424AbiFAKqO (ORCPT ); Wed, 1 Jun 2022 06:46:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50954 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352256AbiFAKqF (ORCPT ); Wed, 1 Jun 2022 06:46:05 -0400 Received: from mail-wr1-x42d.google.com (mail-wr1-x42d.google.com [IPv6:2a00:1450:4864:20::42d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B42980201; Wed, 1 Jun 2022 03:46:01 -0700 (PDT) Received: by mail-wr1-x42d.google.com with SMTP id t6so1772919wra.4; Wed, 01 Jun 2022 03:46:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=v9bZ/oogoWoPQX2w9BuFOFgcjiIV4xqYgwERl5n3obI=; b=JH3JN35t8gUIVD5gD/t3vR8XdbsMT2ectwVKGHqZFksdi+RXnhYrqMff3Qqy5XMzH2 9RsE02JwACIHx6sx2C3/dTXEhy2zVLBjtUAe+kjz/+zeCjn4EQYvWCmKWiu8klp6Knjf 3jCm519DH0+bRF4Sqvt+XWzYqVCNi9lZzK6ZzX7loLfjHg7aCpU3AvMBGlU/1cxliiQJ SexK/iF/+7ddSAlWKZ6kwZFb0FjDFCAEn/BGQUEUZ9OJWEZyFNpqVNh9eBEaRYTz3x/W qnjqxgBqLFKXu85hRC/rwDXBzB1crA2qZ4+B0ccEB7IxjBOHvfq11mQDmzuLf+bKFG2h ikGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=v9bZ/oogoWoPQX2w9BuFOFgcjiIV4xqYgwERl5n3obI=; b=fIa7EQKobK9eWiY6kCULWewuTvgjHoZNKVJANoLmfBA4+47Fl+8lSTe0EwbaBjiEXE Q9UaE4PBYw1AOt4oR0FNUTgPS8KdA0aLjzZIDipbNtJWhmy2JXtGyxobk38nvHJZoXJL BQnpU2+KonjDaU8OtOQpM1f7LdtGO/PrATClQU4HZ8AObDfjq8JwFO4uGvNALWNI1rWI osijb3aj790G/XdtSdCSMUi7JFJkQQRWBBxg72u8obe93owRQwis2klJDav/d4mBcQQA iW9pCUckbjgxTUsPr2ckeHUC77Ti7F79eLs8bSNb8hoH+Hep7xFOal9aP1e3LjXKyfuB o+Wg== X-Gm-Message-State: AOAM531Sw7tVPFbU94oAubU0UyJ+dqQvR+TTHUAUVUaeKlwwj9eRbjCL 7gWf/UApd3qkimvWatBGWoY= X-Google-Smtp-Source: ABdhPJylX4igljmylj1H+c7yVoc6LUNus4KHZ1YGMXQlZ70t1Wz98xKBKsZT3bP4LOukKZ85pNQfww== X-Received: by 2002:a05:6000:18aa:b0:20c:7ec0:b804 with SMTP id b10-20020a05600018aa00b0020c7ec0b804mr51558933wri.128.1654080359423; Wed, 01 Jun 2022 03:45:59 -0700 (PDT) Received: from localhost.localdomain ([77.137.79.96]) by smtp.gmail.com with ESMTPSA id h9-20020a5d4309000000b002102af52a2csm1562150wrq.9.2022.06.01.03.45.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Jun 2022 03:45:58 -0700 (PDT) From: Amir Goldstein To: "Darrick J . Wong" Cc: Dave Chinner , Brian Foster , Christoph Hellwig , Luis Chamberlain , Adam Manzanares , Tyler Hicks , linux-xfs@vger.kernel.org, fstests@vger.kernel.org Subject: [PATCH 5.10 CANDIDATE 4/8] xfs: fix chown leaking delalloc quota blocks when fssetxattr fails Date: Wed, 1 Jun 2022 13:45:43 +0300 Message-Id: <20220601104547.260949-5-amir73il@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220601104547.260949-1-amir73il@gmail.com> References: <20220601104547.260949-1-amir73il@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: fstests@vger.kernel.org From: "Darrick J. Wong" commit 1aecf3734a95f3c167d1495550ca57556d33f7ec upstream. While refactoring the quota code to create a function to allocate inode change transactions, I noticed that xfs_qm_vop_chown_reserve does more than just make reservations: it also *modifies* the incore counts directly to handle the owner id change for the delalloc blocks. I then observed that the fssetxattr code continues validating input arguments after making the quota reservation but before dirtying the transaction. If the routine decides to error out, it fails to undo the accounting switch! This leads to incorrect quota reservation and failure down the line. We can fix this by making the reservation function do only that -- for the new dquot, it reserves ondisk and delalloc blocks to the transaction, and the old dquot hangs on to its incore reservation for now. Once we actually switch the dquots, we can then update the incore reservations because we've dirtied the transaction and it's too late to turn back now. No fixes tag because this has been broken since the start of git. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Reviewed-by: Brian Foster Signed-off-by: Amir Goldstein --- fs/xfs/xfs_qm.c | 92 +++++++++++++++++++------------------------------ 1 file changed, 35 insertions(+), 57 deletions(-) diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c index b2a9abee8b2b..64e5da33733b 100644 --- a/fs/xfs/xfs_qm.c +++ b/fs/xfs/xfs_qm.c @@ -1785,6 +1785,29 @@ xfs_qm_vop_chown( xfs_trans_mod_dquot(tp, newdq, bfield, ip->i_d.di_nblocks); xfs_trans_mod_dquot(tp, newdq, XFS_TRANS_DQ_ICOUNT, 1); + /* + * Back when we made quota reservations for the chown, we reserved the + * ondisk blocks + delalloc blocks with the new dquot. Now that we've + * switched the dquots, decrease the new dquot's block reservation + * (having already bumped up the real counter) so that we don't have + * any reservation to give back when we commit. + */ + xfs_trans_mod_dquot(tp, newdq, XFS_TRANS_DQ_RES_BLKS, + -ip->i_delayed_blks); + + /* + * Give the incore reservation for delalloc blocks back to the old + * dquot. We don't normally handle delalloc quota reservations + * transactionally, so just lock the dquot and subtract from the + * reservation. Dirty the transaction because it's too late to turn + * back now. + */ + tp->t_flags |= XFS_TRANS_DIRTY; + xfs_dqlock(prevdq); + ASSERT(prevdq->q_blk.reserved >= ip->i_delayed_blks); + prevdq->q_blk.reserved -= ip->i_delayed_blks; + xfs_dqunlock(prevdq); + /* * Take an extra reference, because the inode is going to keep * this dquot pointer even after the trans_commit. @@ -1807,84 +1830,39 @@ xfs_qm_vop_chown_reserve( uint flags) { struct xfs_mount *mp = ip->i_mount; - uint64_t delblks; unsigned int blkflags; - struct xfs_dquot *udq_unres = NULL; - struct xfs_dquot *gdq_unres = NULL; - struct xfs_dquot *pdq_unres = NULL; struct xfs_dquot *udq_delblks = NULL; struct xfs_dquot *gdq_delblks = NULL; struct xfs_dquot *pdq_delblks = NULL; - int error; - ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)); ASSERT(XFS_IS_QUOTA_RUNNING(mp)); - delblks = ip->i_delayed_blks; blkflags = XFS_IS_REALTIME_INODE(ip) ? XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS; if (XFS_IS_UQUOTA_ON(mp) && udqp && - i_uid_read(VFS_I(ip)) != udqp->q_id) { + i_uid_read(VFS_I(ip)) != udqp->q_id) udq_delblks = udqp; - /* - * If there are delayed allocation blocks, then we have to - * unreserve those from the old dquot, and add them to the - * new dquot. - */ - if (delblks) { - ASSERT(ip->i_udquot); - udq_unres = ip->i_udquot; - } - } + if (XFS_IS_GQUOTA_ON(ip->i_mount) && gdqp && - i_gid_read(VFS_I(ip)) != gdqp->q_id) { + i_gid_read(VFS_I(ip)) != gdqp->q_id) gdq_delblks = gdqp; - if (delblks) { - ASSERT(ip->i_gdquot); - gdq_unres = ip->i_gdquot; - } - } if (XFS_IS_PQUOTA_ON(ip->i_mount) && pdqp && - ip->i_d.di_projid != pdqp->q_id) { + ip->i_d.di_projid != pdqp->q_id) pdq_delblks = pdqp; - if (delblks) { - ASSERT(ip->i_pdquot); - pdq_unres = ip->i_pdquot; - } - } - - error = xfs_trans_reserve_quota_bydquots(tp, ip->i_mount, - udq_delblks, gdq_delblks, pdq_delblks, - ip->i_d.di_nblocks, 1, flags | blkflags); - if (error) - return error; /* - * Do the delayed blks reservations/unreservations now. Since, these - * are done without the help of a transaction, if a reservation fails - * its previous reservations won't be automatically undone by trans - * code. So, we have to do it manually here. + * Reserve enough quota to handle blocks on disk and reserved for a + * delayed allocation. We'll actually transfer the delalloc + * reservation between dquots at chown time, even though that part is + * only semi-transactional. */ - if (delblks) { - /* - * Do the reservations first. Unreservation can't fail. - */ - ASSERT(udq_delblks || gdq_delblks || pdq_delblks); - ASSERT(udq_unres || gdq_unres || pdq_unres); - error = xfs_trans_reserve_quota_bydquots(NULL, ip->i_mount, - udq_delblks, gdq_delblks, pdq_delblks, - (xfs_qcnt_t)delblks, 0, flags | blkflags); - if (error) - return error; - xfs_trans_reserve_quota_bydquots(NULL, ip->i_mount, - udq_unres, gdq_unres, pdq_unres, - -((xfs_qcnt_t)delblks), 0, blkflags); - } - - return 0; + return xfs_trans_reserve_quota_bydquots(tp, ip->i_mount, udq_delblks, + gdq_delblks, pdq_delblks, + ip->i_d.di_nblocks + ip->i_delayed_blks, + 1, blkflags | flags); } int