From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794061701; b=CszeIzrd+SiR5OuSTpor9DdLbaak5QwYODWpYHr0DDbloQUgbLdpx/x5HeG2pQp79ZxF WRvoYKpdhWCilMDSYwOaa6uskbcRlrFGiAMg7qU+5SF+Sxo7b4c7f/QNjDJtzTSDCZNCc jY99ZMDCB+iUug+O6T2Z76I/FeiRE0Z6sVPd/s0KcBerSwGP3qSpa+tgjDhZB7fav/J5H gyspOVEkIrrTP6t5TfGql/rev2It9lQ/sT1j+2OemhQgaPLlH8tTgqjXiimSfRka7Q6Ex fc6O/YHeCNz5IxYW7T2QbMwBqg6qsbplXJYlxET0B8B6LN4Tvd92/lYDQIzCkuHptkw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794061701; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=4sBpWmm2ZO1XD2xutTNpAgjvF1SZQyaflhccg0KSVYw=; b=I8GUG1oEUALwwyGLYrdUtdjqwiT/wglUtnxBQDzvKTfSdFWOARwXfY4TmxOEC6YI8HA/ uEbND8t/w4Biepv/W1u8X3zD7zmiINu/0rtJokXdmj8xWCJ4WXWnd1L1Q/SpYTPHkIbZr fWhg5XIUWQsHH7d7NRAnMqu/RxH5FPZXLs63/TdDRDSBMeFsRI0M79dKQOvZBpoClrJfu 9ies72sgDCw4XOJnHgMpFMk1ajWxbOAqQgS5Q8JIGW2CAgI1GKZov4jMrKKV7F7TCe6Fs zeVpQs40cj7bZXdPDgIaGov+gqUhWyZd0U6H7i3mmH8u36BM0r6/FcWsfj6J1O5pQDw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=mAJKhAYg; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 84F1B606A326; Sat, 7 Nov 2026 14:28:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=mAJKhAYg Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2EB951F0089F; Sat, 7 Nov 2026 14:28:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794061701; bh=4sBpWmm2ZO1XD2xutTNpAgjvF1SZQyaflhccg0KSVYw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mAJKhAYgkrIWbIj6sJg25r7MUYzIDgwRrCAEYSOnP9TNsSN6xxm8rsy1B3zOhCNn+ N4D9nfu3JDSnXwq7Fl19UwJEjqdfZ6vtnoTLk1GtxY3mECIekIOsHJFRjHq7+QCOBB 2q+M3lDzfHnGG8XLg6ku8D0NYytMBVaOt/W98cQU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Darrick J. Wong" , Christoph Hellwig , Carlos Maiolino Subject: [PATCH 6.12 0743/1536] xfs: only written file data blocks can be shared Date: Sat, 7 Nov 2026 08:45:59 -0500 Message-ID: <20261107135018.395847070@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134957.653319350@linuxfoundation.org> References: <20261107134957.653319350@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Darrick J. Wong commit 634b63baf05062988456a0bd5df2696c14ea2949 upstream. LOLLM noticed that xchk_refcountbt_rmap_check (and its rt equivalent) will count any rmap owner towards the shared count. However, the only blocks that can be shared between xfs files are written file data blocks; and the only blocks that can have single-refcount entries are COW staging extents. Fix the checking code. Cc: stable@vger.kernel.org # v4.16 Fixes: dbde19da963706 ("xfs: cross-reference the rmapbt data with the refcountbt") Signed-off-by: Darrick J. Wong Assisted-by: LOLLM # finding obvious bugs Reviewed-by: Christoph Hellwig Signed-off-by: Carlos Maiolino Signed-off-by: Greg Kroah-Hartman --- fs/xfs/scrub/refcount.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/fs/xfs/scrub/refcount.c +++ b/fs/xfs/scrub/refcount.c @@ -129,6 +129,18 @@ xchk_refcountbt_rmap_check( return 0; } + /* + * The refcount btree should only have records for written file data + * blocks or for COW staging blocks. + */ + if ((XFS_RMAP_NON_INODE_OWNER(rec->rm_owner) && + rec->rm_owner != XFS_RMAP_OWN_COW) || + (rec->rm_flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK | + XFS_RMAP_UNWRITTEN))) { + xchk_btree_xref_set_corrupt(refchk->sc, cur, 0); + return 0; + } + if (rec->rm_startblock <= refchk->bno && rm_last >= rc_last) { /* * The rmap overlaps the refcount record, so we can confirm