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=unavailable 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 E27CCC10F0E for ; Mon, 15 Apr 2019 18:49:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A6AC72087C for ; Mon, 15 Apr 2019 18:49:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555354191; bh=4gxW72HfJr5+kkJDdtE9i6Nz5A/Ke0uzBsjxdhn05vQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fPEUzMjJp5IzeT9OZXuZZYC4VPBsBvzI2lZ+0zofMSHT+OxfTLyDv2AT7wuu71N98 ro/CzycFK0TKKGWPFRScj2EIbUtwG8xjHDtz9P9nqrVZvEsSaN7/aQCbO0VxbIozrg WmR6f0Gbu1JdHr7cho1/wVeoqmJ411H2tR2/Xrnk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728834AbfDOSrI (ORCPT ); Mon, 15 Apr 2019 14:47:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:50204 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728831AbfDOSrH (ORCPT ); Mon, 15 Apr 2019 14:47:07 -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 B60DD218DA; Mon, 15 Apr 2019 18:47:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555354027; bh=4gxW72HfJr5+kkJDdtE9i6Nz5A/Ke0uzBsjxdhn05vQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PkTF9hlgAkQTg2ur8jdoQygXNC9hTUet7w53TiMmIVwdeg+y0J52aSM4D2pNqx1gH qOhyEMlpatMkJ4TCnvB0wvHAQYEOYoxtzCP5wOzoUxzf+jS/gWH5lrC1ELYTkduNvV jH4TeprnxY6GDbosyGmC08MUOmcl4Bynllzwb4Fw= 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 4.9 45/76] arm64: kaslr: Reserve size of ARM64_MEMSTART_ALIGN in linear region Date: Mon, 15 Apr 2019 20:44:09 +0200 Message-Id: <20190415183720.131293717@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190415183707.712011689@linuxfoundation.org> References: <20190415183707.712011689@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 fa6b2fad7a3d..5d3df68272f5 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -272,7 +272,7 @@ 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