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=-10.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_MED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 C4F74C43142 for ; Mon, 25 Jun 2018 22:41:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7287F2620F for ; Mon, 25 Jun 2018 22:41:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="JTPUZE/G" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7287F2620F Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933627AbeFYWlP (ORCPT ); Mon, 25 Jun 2018 18:41:15 -0400 Received: from mail-yw0-f202.google.com ([209.85.161.202]:42839 "EHLO mail-yw0-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932200AbeFYWlM (ORCPT ); Mon, 25 Jun 2018 18:41:12 -0400 Received: by mail-yw0-f202.google.com with SMTP id c79-v6so6369593ywh.9 for ; Mon, 25 Jun 2018 15:41:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:date:in-reply-to:message-id:references:subject:from:to :cc; bh=O8CLfxcg9OKod1ivZbkoSyCm0ci4+lg3Z3Y3PZu7UvE=; b=JTPUZE/GxynGfFI/4iONF3uw/WeFYQQ6M8VlMNpH0ZU14R2j6KAhlDygiRO8VAM6mA ZdcZeH12M1U29XH1GW8SRT0wgsbQRIbdMDswzReTGwaA0leh5WI03ZFGy0y7Dl49vAU5 Sug/SHF5odExmWhLk9f4hadKAg3Tgyk5CprBUgh74KSIeH94nJmc/MD1uB60tFkq+POa h1k9A2kw3lVjvWiwSu4MGNl5eJm2gngU04RttYcXYlRJQMv8KMkK3JIQTn6sLq0AlEhe 91aP9Do3SAyXhpoRrxYL+ajHGHFbE/Ya+FyYKgV5DQClYCY9iiK4KNd0qjCCaCtUx4zd jcZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:in-reply-to:message-id :references:subject:from:to:cc; bh=O8CLfxcg9OKod1ivZbkoSyCm0ci4+lg3Z3Y3PZu7UvE=; b=m9LwhqRqFQAtAUy2B10QKqExn8PCpU6KSMg7eOr9kqYbdgrjoly/GjrnUD+rKiy1C8 MkAKXx6GQGjwdUpasyHq73SoDupxblFycRfl1VSMEfUf3RhBXO61w4RNte76bL1pIT1e 8/kD2aoHcaBpzCJoGG1kSIDVaDSPGy5S0Mnjujxfn2Vxzs/aSjvU7brGUWGVlBjMwZFe ddJz5wB+JH7MZPVzaxWYENnCUHjPFv81Ih49UqDda2u5jk7XOMp8e5y7cH8eG+G+gQDg WmkCV9fbTsS/2FJ4GEQotqcr0fsU1I3HJAM/4jWeZuDUGpqEFqKmol09RXbEZShKPOsB WRew== X-Gm-Message-State: APt69E3wIloNimPdSyrA0vrrqaah8egjMwXeOOrQY2JGSiZwnKSgwQEm V1pATyBnNGUgQBno7x4Wj2SZD1gq82+1Uw== X-Google-Smtp-Source: ADUXVKIZhgOfpWOU7eftUZZ/WQuPZZDkCs20b0atPoQ+qjy3MlJIB7NY/ZTFjvwbwXinU8dvuEvN7+PTWr1jsQ== MIME-Version: 1.0 X-Received: by 2002:a25:ba8c:: with SMTP id s12-v6mr4018875ybg.6.1529966472111; Mon, 25 Jun 2018 15:41:12 -0700 (PDT) Date: Mon, 25 Jun 2018 15:38:54 -0700 In-Reply-To: <20180625224014.134829-1-thgarnie@google.com> Message-Id: <20180625224014.134829-7-thgarnie@google.com> References: <20180625224014.134829-1-thgarnie@google.com> X-Mailer: git-send-email 2.18.0.rc2.346.g013aa6912e-goog Subject: [PATCH v5 06/27] x86/entry/64: Adapt assembly for PIE support From: Thomas Garnier To: kernel-hardening@lists.openwall.com Cc: Thomas Garnier , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, "Kirill A. Shutemov" , Tom Lendacky , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Change the assembly code to use only relative references of symbols for the kernel to be PIE compatible. Position Independent Executable (PIE) support will allow to extend the KASLR randomization range 0xffffffff80000000. Signed-off-by: Thomas Garnier --- arch/x86/entry/entry_64.S | 18 ++++++++++++------ arch/x86/kernel/relocate_kernel_64.S | 8 +++----- 2 files changed, 15 insertions(+), 11 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index c6f3677e6105..e738d8d0e308 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -191,7 +191,7 @@ ENTRY(entry_SYSCALL_64_trampoline) * spill RDI and restore it in a second-stage trampoline. */ pushq %rdi - movq $entry_SYSCALL_64_stage2, %rdi + movabsq $entry_SYSCALL_64_stage2, %rdi JMP_NOSPEC %rdi END(entry_SYSCALL_64_trampoline) @@ -1277,7 +1277,8 @@ ENTRY(error_entry) movl %ecx, %eax /* zero extend */ cmpq %rax, RIP+8(%rsp) je .Lbstep_iret - cmpq $.Lgs_change, RIP+8(%rsp) + leaq .Lgs_change(%rip), %rcx + cmpq %rcx, RIP+8(%rsp) jne .Lerror_entry_done /* @@ -1482,10 +1483,10 @@ ENTRY(nmi) * resume the outer NMI. */ - movq $repeat_nmi, %rdx + leaq repeat_nmi(%rip), %rdx cmpq 8(%rsp), %rdx ja 1f - movq $end_repeat_nmi, %rdx + leaq end_repeat_nmi(%rip), %rdx cmpq 8(%rsp), %rdx ja nested_nmi_out 1: @@ -1539,7 +1540,8 @@ nested_nmi: pushq %rdx pushfq pushq $__KERNEL_CS - pushq $repeat_nmi + leaq repeat_nmi(%rip), %rdx + pushq %rdx /* Put stack back */ addq $(6*8), %rsp @@ -1578,7 +1580,11 @@ first_nmi: addq $8, (%rsp) /* Fix up RSP */ pushfq /* RFLAGS */ pushq $__KERNEL_CS /* CS */ - pushq $1f /* RIP */ + pushq $0 /* Futur return address */ + pushq %rax /* Save RAX */ + leaq 1f(%rip), %rax /* RIP */ + movq %rax, 8(%rsp) /* Put 1f on return address */ + popq %rax /* Restore RAX */ iretq /* continues at repeat_nmi below */ UNWIND_HINT_IRET_REGS 1: diff --git a/arch/x86/kernel/relocate_kernel_64.S b/arch/x86/kernel/relocate_kernel_64.S index a7227dfe1a2b..0c0fc259a4e2 100644 --- a/arch/x86/kernel/relocate_kernel_64.S +++ b/arch/x86/kernel/relocate_kernel_64.S @@ -208,11 +208,9 @@ identity_mapped: movq %rax, %cr3 lea PAGE_SIZE(%r8), %rsp call swap_pages - jmp *virtual_mapped_addr(%rip) - - /* Absolute value for PIE support */ -virtual_mapped_addr: - .quad virtual_mapped + movabsq $virtual_mapped, %rax + pushq %rax + ret virtual_mapped: movq RSP(%r8), %rsp -- 2.18.0.rc2.346.g013aa6912e-goog