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=-15.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 661F4C433E6 for ; Thu, 21 Jan 2021 21:38:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3AB8C23A5C for ; Thu, 21 Jan 2021 21:38:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727767AbhAUViM (ORCPT ); Thu, 21 Jan 2021 16:38:12 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:35055 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727173AbhAUVbr (ORCPT ); Thu, 21 Jan 2021 16:31:47 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611264620; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1j9FCObNnzT+7dQqGeu7CZnMn7yEU2Jc3x2oWWCHzac=; b=dmEEcUZQrz1gOvDPDf9fSv8ssxChZ2KMBgKwuQemvzIBGvRgzxjNT5zVk0fp+9uOFBQncr M+jhZ5FHJ0j20ulMK21d8cJDpb+2wgX0wZFEPx/viFyoquUPH4EZjy0gT0JN/57++XBmS0 5ftPrenp7EhJLvplGlGAKYxDAsjIurg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-534-RYZkcDLiMnmQ7XJKIwJRrw-1; Thu, 21 Jan 2021 16:30:15 -0500 X-MC-Unique: RYZkcDLiMnmQ7XJKIwJRrw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5DA61806661; Thu, 21 Jan 2021 21:30:13 +0000 (UTC) Received: from treble.redhat.com (ovpn-116-102.rdu2.redhat.com [10.10.116.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3857B19C59; Thu, 21 Jan 2021 21:30:12 +0000 (UTC) From: Josh Poimboeuf To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Sami Tolvanen , Sedat Dilek , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, Miroslav Benes , Juergen Gross , Boris Ostrovsky Subject: [PATCH v2 12/20] x86/xen: Support objtool validation in xen-asm.S Date: Thu, 21 Jan 2021 15:29:28 -0600 Message-Id: <8b042a09c69e8645f3b133ef6653ba28f896807d.1611263462.git.jpoimboe@redhat.com> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The OBJECT_FILES_NON_STANDARD annotation is used to tell objtool to ignore a file. File-level ignores won't work when validating vmlinux.o. Tweak the ELF metadata and unwind hints to allow objtool to follow the code. Cc: Juergen Gross Reviewed-by: Boris Ostrovsky Signed-off-by: Josh Poimboeuf --- arch/x86/xen/Makefile | 1 - arch/x86/xen/xen-asm.S | 29 +++++++++++++++++++---------- 2 files changed, 19 insertions(+), 11 deletions(-) diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile index fc5c5ba4aacb..40b5779fce21 100644 --- a/arch/x86/xen/Makefile +++ b/arch/x86/xen/Makefile @@ -1,5 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 -OBJECT_FILES_NON_STANDARD_xen-asm.o := y ifdef CONFIG_FUNCTION_TRACER # Do not profile debug and lowlevel utilities diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S index 1cb0e84b9161..a05e80b552c0 100644 --- a/arch/x86/xen/xen-asm.S +++ b/arch/x86/xen/xen-asm.S @@ -14,6 +14,7 @@ #include #include #include +#include #include @@ -146,6 +147,7 @@ SYM_FUNC_END(xen_read_cr2_direct); .macro xen_pv_trap name SYM_CODE_START(xen_\name) + UNWIND_HINT_EMPTY pop %rcx pop %r11 jmp \name @@ -184,6 +186,7 @@ xen_pv_trap asm_exc_xen_hypervisor_callback SYM_CODE_START(xen_early_idt_handler_array) i = 0 .rept NUM_EXCEPTION_VECTORS + UNWIND_HINT_EMPTY pop %rcx pop %r11 jmp early_idt_handler_array + i*EARLY_IDT_HANDLER_SIZE @@ -210,11 +213,13 @@ hypercall_iret = hypercall_page + __HYPERVISOR_iret * 32 * rsp->rax } */ SYM_CODE_START(xen_iret) + UNWIND_HINT_EMPTY pushq $0 jmp hypercall_iret SYM_CODE_END(xen_iret) SYM_CODE_START(xen_sysret64) + UNWIND_HINT_EMPTY /* * We're already on the usermode stack at this point, but * still with the kernel gs, so we can easily switch back. @@ -250,7 +255,8 @@ SYM_CODE_END(xen_sysret64) */ /* Normal 64-bit system call target */ -SYM_FUNC_START(xen_syscall_target) +SYM_CODE_START(xen_syscall_target) + UNWIND_HINT_EMPTY popq %rcx popq %r11 @@ -263,12 +269,13 @@ SYM_FUNC_START(xen_syscall_target) movq $__USER_CS, 1*8(%rsp) jmp entry_SYSCALL_64_after_hwframe -SYM_FUNC_END(xen_syscall_target) +SYM_CODE_END(xen_syscall_target) #ifdef CONFIG_IA32_EMULATION /* 32-bit compat syscall target */ -SYM_FUNC_START(xen_syscall32_target) +SYM_CODE_START(xen_syscall32_target) + UNWIND_HINT_EMPTY popq %rcx popq %r11 @@ -281,10 +288,11 @@ SYM_FUNC_START(xen_syscall32_target) movq $__USER32_CS, 1*8(%rsp) jmp entry_SYSCALL_compat_after_hwframe -SYM_FUNC_END(xen_syscall32_target) +SYM_CODE_END(xen_syscall32_target) /* 32-bit compat sysenter target */ -SYM_FUNC_START(xen_sysenter_target) +SYM_CODE_START(xen_sysenter_target) + UNWIND_HINT_EMPTY /* * NB: Xen is polite and clears TF from EFLAGS for us. This means * that we don't need to guard against single step exceptions here. @@ -301,17 +309,18 @@ SYM_FUNC_START(xen_sysenter_target) movq $__USER32_CS, 1*8(%rsp) jmp entry_SYSENTER_compat_after_hwframe -SYM_FUNC_END(xen_sysenter_target) +SYM_CODE_END(xen_sysenter_target) #else /* !CONFIG_IA32_EMULATION */ -SYM_FUNC_START_ALIAS(xen_syscall32_target) -SYM_FUNC_START(xen_sysenter_target) +SYM_CODE_START(xen_syscall32_target) +SYM_CODE_START(xen_sysenter_target) + UNWIND_HINT_EMPTY lea 16(%rsp), %rsp /* strip %rcx, %r11 */ mov $-ENOSYS, %rax pushq $0 jmp hypercall_iret -SYM_FUNC_END(xen_sysenter_target) -SYM_FUNC_END_ALIAS(xen_syscall32_target) +SYM_CODE_END(xen_sysenter_target) +SYM_CODE_END(xen_syscall32_target) #endif /* CONFIG_IA32_EMULATION */ -- 2.29.2