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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 EFF68C2BB85 for ; Fri, 10 Apr 2020 03:49:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C7DCA20BED for ; Fri, 10 Apr 2020 03:49:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586490591; bh=Gf392KoCBUhgkrXocXreLB3YDk6gRHSO655nXvCucgw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0OlE04tebV2fqtJiZp4uYLvSnY7/hQYkpMVjhww9oCEvTkZ0YbVXtqxbd38xDCkU8 EsptxErDAHb1ySUagMwlzCrpKDZ3eNdtyq52b3DMDBTUBAhN0Q/YHm0zMXdOIGUU43 3TuWphPx9qHlVCRSdE9ViDBgA+brB9z3ESvMgcVY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728684AbgDJDtu (ORCPT ); Thu, 9 Apr 2020 23:49:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:33864 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728631AbgDJDto (ORCPT ); Thu, 9 Apr 2020 23:49:44 -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 408B020936; Fri, 10 Apr 2020 03:49:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586490583; bh=Gf392KoCBUhgkrXocXreLB3YDk6gRHSO655nXvCucgw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aUKL5Q8fz39zfTP25OOlOs1GOgNB+D1oBUHwcz4WbqT33wtLO5NoM7G4tn7cXJGTz eKdY0c6rAIJupfFRSaP0ACcuUwUIVvGPzNIDGZBJL20VlVOABMArIidxtPlVyVbSab bFNpxHHgFaQqLCyuxNOsatAzKzpVKQMCoZY79keI= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Arvind Sankar , Ard Biesheuvel , Ingo Molnar , Sasha Levin Subject: [PATCH AUTOSEL 5.4 29/46] x86/boot: Use unsigned comparison for addresses Date: Thu, 9 Apr 2020 23:48:52 -0400 Message-Id: <20200410034909.8922-29-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200410034909.8922-1-sashal@kernel.org> References: <20200410034909.8922-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arvind Sankar [ Upstream commit 81a34892c2c7c809f9c4e22c5ac936ae673fb9a2 ] The load address is compared with LOAD_PHYSICAL_ADDR using a signed comparison currently (using jge instruction). When loading a 64-bit kernel using the new efi32_pe_entry() point added by: 97aa276579b2 ("efi/x86: Add true mixed mode entry point into .compat section") using Qemu with -m 3072, the firmware actually loads us above 2Gb, resulting in a very early crash. Use the JAE instruction to perform a unsigned comparison instead, as physical addresses should be considered unsigned. Signed-off-by: Arvind Sankar Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20200301230436.2246909-6-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-14-ardb@kernel.org Signed-off-by: Sasha Levin --- arch/x86/boot/compressed/head_32.S | 2 +- arch/x86/boot/compressed/head_64.S | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S index 5e30eaaf8576f..70ffce98c5683 100644 --- a/arch/x86/boot/compressed/head_32.S +++ b/arch/x86/boot/compressed/head_32.S @@ -106,7 +106,7 @@ ENTRY(startup_32) notl %eax andl %eax, %ebx cmpl $LOAD_PHYSICAL_ADDR, %ebx - jge 1f + jae 1f #endif movl $LOAD_PHYSICAL_ADDR, %ebx 1: diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index e9a7f7cadb121..07d2002da642a 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -106,7 +106,7 @@ ENTRY(startup_32) notl %eax andl %eax, %ebx cmpl $LOAD_PHYSICAL_ADDR, %ebx - jge 1f + jae 1f #endif movl $LOAD_PHYSICAL_ADDR, %ebx 1: @@ -297,7 +297,7 @@ ENTRY(startup_64) notq %rax andq %rax, %rbp cmpq $LOAD_PHYSICAL_ADDR, %rbp - jge 1f + jae 1f #endif movq $LOAD_PHYSICAL_ADDR, %rbp 1: -- 2.20.1