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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 F3839C10F12 for ; Mon, 15 Apr 2019 19:02:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C2016218FC for ; Mon, 15 Apr 2019 19:02:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555354962; bh=6Ai6kGjJWEbGw37IbbQbxsmFWPVI252hG3ClNzAzMEY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tX02Jp91OMyrU1k41QcVkPaqJDNKnJUUXDvg+8B89ziCv6H3PSIMnScCzpZbbxBVa aQCi07gktvUKwxouhVq0JjOzin3OfcCzT8r5jui4OcxUNG/CVHZDbEz4N8LXude4M4 8qb0y33cGzl7xBhvqqzyvAcy1I78PG0dDVXilM4s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728942AbfDOTCl (ORCPT ); Mon, 15 Apr 2019 15:02:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:33706 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728885AbfDOTCh (ORCPT ); Mon, 15 Apr 2019 15:02:37 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 B173F21906; Mon, 15 Apr 2019 19:02:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555354956; bh=6Ai6kGjJWEbGw37IbbQbxsmFWPVI252hG3ClNzAzMEY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DnRiEe6xjU2DyzYXzJnLwWuDCNf0QFPM68O3VOUFVOLPYJgaDQoCc+vKYEFyX9lbT LR4zG1g4EJCgoUoFaEETHwEKFY7sF4cejDj9Pb5ZEZZCpD/cuChNR9pYQIcGKrfZ03 av4MMnzijXd9HBexVYYfDL99S4ovtIs5Vvakftwc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ard Biesheuvel , liyueyi , Will Deacon , "Sasha Levin (Microsoft)" Subject: [PATCH 4.14 13/69] arm64: kaslr: Reserve size of ARM64_MEMSTART_ALIGN in linear region Date: Mon, 15 Apr 2019 20:58:31 +0200 Message-Id: <20190415183729.452650602@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190415183726.036654568@linuxfoundation.org> References: <20190415183726.036654568@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit c8a43c18a97845e7f94ed7d181c11f41964976a2 ] When KASLR is enabled (CONFIG_RANDOMIZE_BASE=y), the top 4K of kernel virtual address space may be mapped to physical addresses despite being reserved for ERR_PTR values. Fix the randomization of the linear region so that we avoid mapping the last page of the virtual address space. Cc: Ard Biesheuvel Signed-off-by: liyueyi [will: rewrote commit message; merged in suggestion from Ard] Signed-off-by: Will Deacon Signed-off-by: Sasha Levin (Microsoft) --- arch/arm64/mm/init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index caa295cd5d09..9e6c822d458d 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -447,7 +447,7 @@ void __init arm64_memblock_init(void) * memory spans, randomize the linear region as well. */ if (memstart_offset_seed > 0 && range >= ARM64_MEMSTART_ALIGN) { - range = range / ARM64_MEMSTART_ALIGN + 1; + range /= ARM64_MEMSTART_ALIGN; memstart_addr -= ARM64_MEMSTART_ALIGN * ((range * memstart_offset_seed) >> 16); } -- 2.19.1