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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 A114CC433DF for ; Sun, 18 Oct 2020 19:56:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6723222268 for ; Sun, 18 Oct 2020 19:56:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603051019; bh=OUR4xePPL/uT6nw4O/uyuUsxy+afCtN8euw1cYdPSTU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=J51Hml9lCel5KjTgwj/+8rYuURselcplZc16hQUdU8nRGyvtal0R1NXvIPOwJtLjv qZGRctFiLxdPF22H00bDHOGkVziA3Dz3zBvE4nAC0kqQcEoANxYEqVPxOryaevU+zd +8+l0JmAVU3bWVrm1l5KTbvaNkYao7NS1Ip4pU9A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388268AbgJRT46 (ORCPT ); Sun, 18 Oct 2020 15:56:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:58188 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728263AbgJRTTa (ORCPT ); Sun, 18 Oct 2020 15:19:30 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6E0BC222B9; Sun, 18 Oct 2020 19:19:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603048770; bh=OUR4xePPL/uT6nw4O/uyuUsxy+afCtN8euw1cYdPSTU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ppfgbssk634WTaVw1RYASXsKTQZXSTaekPSxjdtHWewSB3s0ylll+tyKbcl+v+igK sh68sOTc7OoKVA+kxYBQhXXS5Ie5Je6t8OUhWswd+D9W94rbp2uqNnXA0UA7EIkpY+ veluTnQDg8ft60/1bdNjH1x37byGh47zCGfYItwI= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Darrick J. Wong" , Christoph Hellwig , Sasha Levin , linux-xfs@vger.kernel.org Subject: [PATCH AUTOSEL 5.9 069/111] xfs: make sure the rt allocator doesn't run off the end Date: Sun, 18 Oct 2020 15:17:25 -0400 Message-Id: <20201018191807.4052726-69-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201018191807.4052726-1-sashal@kernel.org> References: <20201018191807.4052726-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: "Darrick J. Wong" [ Upstream commit 2a6ca4baed620303d414934aa1b7b0a8e7bab05f ] There's an overflow bug in the realtime allocator. If the rt volume is large enough to handle a single allocation request that is larger than the maximum bmap extent length and the rt bitmap ends exactly on a bitmap block boundary, it's possible that the near allocator will try to check the freeness of a range that extends past the end of the bitmap. This fails with a corruption error and shuts down the fs. Therefore, constrain maxlen so that the range scan cannot run off the end of the rt bitmap. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Sasha Levin --- fs/xfs/xfs_rtalloc.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c index 6209e7b6b895b..86994d7f7cba3 100644 --- a/fs/xfs/xfs_rtalloc.c +++ b/fs/xfs/xfs_rtalloc.c @@ -247,6 +247,9 @@ xfs_rtallocate_extent_block( end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1; i <= end; i++) { + /* Make sure we don't scan off the end of the rt volume. */ + maxlen = min(mp->m_sb.sb_rextents, i + maxlen) - i; + /* * See if there's a free extent of maxlen starting at i. * If it's not so then next will contain the first non-free. @@ -442,6 +445,14 @@ xfs_rtallocate_extent_near( */ if (bno >= mp->m_sb.sb_rextents) bno = mp->m_sb.sb_rextents - 1; + + /* Make sure we don't run off the end of the rt volume. */ + maxlen = min(mp->m_sb.sb_rextents, bno + maxlen) - bno; + if (maxlen < minlen) { + *rtblock = NULLRTBLOCK; + return 0; + } + /* * Try the exact allocation first. */ -- 2.25.1