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=-9.8 required=3.0 tests=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 9AA47C76186 for ; Thu, 18 Jul 2019 03:05:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 719232184E for ; Thu, 18 Jul 2019 03:05:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563419109; bh=SZLtCnvDrzAG+3SlFn47Lfe9Tc9P9rbtJ9EMIqcWHuU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=apnyRM/HUwcH2MziScTkmNEpHnwWSSh+VGzZn3HHrO0nmA07k1FD3Wv3a/PcUn4N9 Zm3UHW5lbUvBmPKwsBwhOGBi/YTwTczdSn386enwg+LdIaRGfZm7Ukm7DXYW+Xmey0 WSJBkoQkO9WWAGM3pxeWOFt2O5bOCc69q94uxNEA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389880AbfGRDFI (ORCPT ); Wed, 17 Jul 2019 23:05:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:36086 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389853AbfGRDFG (ORCPT ); Wed, 17 Jul 2019 23:05:06 -0400 Received: from localhost (115.42.148.210.bf.2iij.net [210.148.42.115]) (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 B17352173B; Thu, 18 Jul 2019 03:05:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563419105; bh=SZLtCnvDrzAG+3SlFn47Lfe9Tc9P9rbtJ9EMIqcWHuU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UCuQ/bb5ovyAfRxTDz3V5AZVN1UIlNhbH8uK18l0/hlFSGVop3+85xr1ZwWvxGKDX iIjJPl1VaQSaTd6HChMa0eJetbVDEVT9SSlO9aqbyIud1R0LN9faZomam+945pdXn1 HQcBXGOSj94XzMpb6u7bZlzmNYXegUZi2ZQG4Vfw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Kirill A. Shutemov" , Thomas Gleixner , Borislav Petkov , "H. Peter Anvin" , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Alexander Potapenko , Sasha Levin Subject: [PATCH 5.1 31/54] x86/boot/64: Add missing fixup_pointer() for next_early_pgt access Date: Thu, 18 Jul 2019 12:01:26 +0900 Message-Id: <20190718030055.748720665@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190718030053.287374640@linuxfoundation.org> References: <20190718030053.287374640@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 c1887159eb48ba40e775584cfb2a443962cf1a05 ] __startup_64() uses fixup_pointer() to access global variables in a position-independent fashion. Access to next_early_pgt was wrapped into the helper, but one instance in the 5-level paging branch was missed. GCC generates a R_X86_64_PC32 PC-relative relocation for the access which doesn't trigger the issue, but Clang emmits a R_X86_64_32S which leads to an invalid memory access and system reboot. Fixes: 187e91fe5e91 ("x86/boot/64/clang: Use fixup_pointer() to access 'next_early_pgt'") Signed-off-by: Kirill A. Shutemov Signed-off-by: Thomas Gleixner Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: Dave Hansen Cc: Andy Lutomirski Cc: Peter Zijlstra Cc: Alexander Potapenko Link: https://lkml.kernel.org/r/20190620112422.29264-1-kirill.shutemov@linux.intel.com Signed-off-by: Sasha Levin --- arch/x86/kernel/head64.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 7df5bce4e1be..29ffa495bd1c 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -184,7 +184,8 @@ unsigned long __head __startup_64(unsigned long physaddr, pgtable_flags = _KERNPG_TABLE_NOENC + sme_get_me_mask(); if (la57) { - p4d = fixup_pointer(early_dynamic_pgts[next_early_pgt++], physaddr); + p4d = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++], + physaddr); i = (physaddr >> PGDIR_SHIFT) % PTRS_PER_PGD; pgd[i + 0] = (pgdval_t)p4d + pgtable_flags; -- 2.20.1