From patchwork Tue Oct 27 13:50:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 290153 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, 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 3BC6DC55179 for ; Tue, 27 Oct 2020 14:07:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E81CB22281 for ; Tue, 27 Oct 2020 14:07:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603807632; bh=JtyqfGX6OHLmksouCsKV/dd0WzwG4r/Mqs67QCAqv88=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=thx5vbqIL+ZcO039sGGwQdSObnE7khNbJun4MQkpv0w3C6i66XppdfGgg7l0vprcJ b852xDhFk7dzAJ46Ew02xvYGrUGYdsb1seU2DuyL90fZqa9ypGJlshGwLEM+J0XSGo gcuK9DyuLHM2nc6ByCmzA/XWrA59KJ5G1lVDHLGU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754807AbgJ0OHK (ORCPT ); Tue, 27 Oct 2020 10:07:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:55808 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754803AbgJ0OHJ (ORCPT ); Tue, 27 Oct 2020 10:07:09 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 7A4E022263; Tue, 27 Oct 2020 14:07:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603807629; bh=JtyqfGX6OHLmksouCsKV/dd0WzwG4r/Mqs67QCAqv88=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nvBPudVtYX9vqWsRhyP3AHX41BLU9T2U4fmZF2pusP1OKWMOavwS+Lwxh9n8OOZHp vcHJteAPWyWNV5G6bOxW8B/xPkBGr+pifMbOv760lCkD9uCIrNzmUOIdBthVPXD4XN DmFPzEHXHg/xBxFcZUODpz9BQ4JHEcMcUslnRLPo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Darrick J. Wong" , Christoph Hellwig , Sasha Levin Subject: [PATCH 4.9 122/139] xfs: make sure the rt allocator doesnt run off the end Date: Tue, 27 Oct 2020 14:50:16 +0100 Message-Id: <20201027134907.936415606@linuxfoundation.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201027134902.130312227@linuxfoundation.org> References: <20201027134902.130312227@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 0d93d3c10fcc4..d812f84252d5b 100644 --- a/fs/xfs/xfs_rtalloc.c +++ b/fs/xfs/xfs_rtalloc.c @@ -257,6 +257,9 @@ 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. @@ -448,6 +451,14 @@ 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. */