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=-8.7 required=3.0 tests=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 2DBFEC43613 for ; Thu, 20 Jun 2019 11:24:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 033CB2080C for ; Thu, 20 Jun 2019 11:24:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=shutemov-name.20150623.gappssmtp.com header.i=@shutemov-name.20150623.gappssmtp.com header.b="TvNlbhsx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731557AbfFTLY0 (ORCPT ); Thu, 20 Jun 2019 07:24:26 -0400 Received: from mail-ed1-f67.google.com ([209.85.208.67]:38621 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726491AbfFTLY0 (ORCPT ); Thu, 20 Jun 2019 07:24:26 -0400 Received: by mail-ed1-f67.google.com with SMTP id r12so4205119edo.5 for ; Thu, 20 Jun 2019 04:24:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=LjM0cV/bj1P72dFe0nedZsKK4znRV88KKfVEX7k49WY=; b=TvNlbhsxVxOOqpPMrv/TSKNadKbnq/OOB32FLW8FOsWPBI+zHlAs3XT0wYYg4pjcod ghodAtJ9UyrWY+galSIg2HhrrzFJFoa+Nf/SOkwnaFgYEbjZWT7lqrZhkOa0Y7LTYbAj PM1KPPcHsP2gJmjrijblAneAds+cNGf3Pk7K0HkbYTx+HjM61HuR+/Yd5qfL+XKjQ9Bd KJeUb2yQ3CmE261znSts/ye4KC5y8/e37XoNqAk7CMnupNB+2s1pIQ7RlpkB1bGR5f8U WwmLCZYfuXvK+XbxzAV67OetxoiibSXHH3KLcaccHM6XeUK5nKmplvo1Ua0vg2+LtsGU 4zgQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=LjM0cV/bj1P72dFe0nedZsKK4znRV88KKfVEX7k49WY=; b=mj1IlB/Iyk0adhYMemb3XPOeMlvfzqr4KXkuLG/HAMPO9iyGwOf/fKT/xPrLmD/TSu GK10JOBFImcfkopJXMcbt3RtRmJ5K7KXvsFy10j9bLAd9Z63Xp/wjlgQKm9QJCgDXVbg UUUZZ49AAutrlM5qiQ+L/iJAUpBwLJGQg633heJMqoqa62L4rUp3inTf3BAQhgkozVvZ HEak3X/jOii1xlYFa4W92fEBIdRYJFyoH2WJjcJLlf5RAWNNdCxP8ezbT5o7fvr+DM9h 5qD1G8a5RXhpsF6GGBzFYMqkjuVfdW30GtwQdBVq4q7hLaDOTS5QL5VKBbSgXylhuXzT GvSA== X-Gm-Message-State: APjAAAXYOKSD78+bwK5WiI8TpSza3TqFXOK5RW06D6U8Pkq9ubbtef6D FBzBpcV3/NR6IAPShWv45xNpXw== X-Google-Smtp-Source: APXvYqxjOnXArZRjN7nJvFwzbquqB+n5nJGhIi+Izhsa0OZPDtvs3ljpYNfxEDpaVMv3ztyfFodH6Q== X-Received: by 2002:a50:a544:: with SMTP id z4mr1460519edb.71.1561029864584; Thu, 20 Jun 2019 04:24:24 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id o93sm6508189edd.46.2019.06.20.04.24.23 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 20 Jun 2019 04:24:23 -0700 (PDT) From: "Kirill A. Shutemov" X-Google-Original-From: "Kirill A. Shutemov" Received: by box.localdomain (Postfix, from userid 1000) id 333F31040F8; Thu, 20 Jun 2019 14:24:25 +0300 (+03) To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Dave Hansen , Andy Lutomirski , Peter Zijlstra Cc: x86@kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , Alexander Potapenko Subject: [PATCH] x86/boot/64: Fix missed fixup_pointer() for next_early_pgt access Date: Thu, 20 Jun 2019 14:24:22 +0300 Message-Id: <20190620112422.29264-1-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org __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 of the instance in 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 and system reboot. Signed-off-by: Kirill A. Shutemov Fixes: 187e91fe5e91 ("x86/boot/64/clang: Use fixup_pointer() to access 'next_early_pgt'") Cc: Alexander Potapenko --- arch/x86/kernel/head64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 16b1cbd3a61e..4d98ba8063d1 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -184,7 +184,7 @@ 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; -- 2.21.0