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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 5FF19C67790 for ; Fri, 27 Jul 2018 10:01:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F15F2089A for ; Fri, 27 Jul 2018 10:01:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1F15F2089A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org 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 S2388782AbeG0LWw (ORCPT ); Fri, 27 Jul 2018 07:22:52 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:34158 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730120AbeG0LWv (ORCPT ); Fri, 27 Jul 2018 07:22:51 -0400 Received: from localhost (unknown [89.188.5.116]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id B6BC5CBA; Fri, 27 Jul 2018 10:01:41 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Boris Ostrovsky , Juergen Gross , Jason Andryuk Subject: [PATCH 4.14 04/48] xen/PVH: Set up GS segment for stack canary Date: Fri, 27 Jul 2018 11:59:49 +0200 Message-Id: <20180727095918.941271116@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180727095918.503549522@linuxfoundation.org> References: <20180727095918.503549522@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 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 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Boris Ostrovsky commit 98014068328c5574de9a4a30b604111fd9d8f901 upstream. We are making calls to C code (e.g. xen_prepare_pvh()) which may use stack canary (stored in GS segment). Signed-off-by: Boris Ostrovsky Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Cc: Jason Andryuk Signed-off-by: Greg Kroah-Hartman --- arch/x86/xen/xen-pvh.S | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) --- a/arch/x86/xen/xen-pvh.S +++ b/arch/x86/xen/xen-pvh.S @@ -54,6 +54,9 @@ * charge of setting up it's own stack, GDT and IDT. */ +#define PVH_GDT_ENTRY_CANARY 4 +#define PVH_CANARY_SEL (PVH_GDT_ENTRY_CANARY * 8) + ENTRY(pvh_start_xen) cld @@ -98,6 +101,12 @@ ENTRY(pvh_start_xen) /* 64-bit entry point. */ .code64 1: + /* Set base address in stack canary descriptor. */ + mov $MSR_GS_BASE,%ecx + mov $_pa(canary), %eax + xor %edx, %edx + wrmsr + call xen_prepare_pvh /* startup_64 expects boot_params in %rsi. */ @@ -107,6 +116,17 @@ ENTRY(pvh_start_xen) #else /* CONFIG_X86_64 */ + /* Set base address in stack canary descriptor. */ + movl $_pa(gdt_start),%eax + movl $_pa(canary),%ecx + movw %cx, (PVH_GDT_ENTRY_CANARY * 8) + 2(%eax) + shrl $16, %ecx + movb %cl, (PVH_GDT_ENTRY_CANARY * 8) + 4(%eax) + movb %ch, (PVH_GDT_ENTRY_CANARY * 8) + 7(%eax) + + mov $PVH_CANARY_SEL,%eax + mov %eax,%gs + call mk_early_pgtbl_32 mov $_pa(initial_page_table), %eax @@ -150,9 +170,13 @@ gdt_start: .quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* __KERNEL_CS */ #endif .quad GDT_ENTRY(0xc092, 0, 0xfffff) /* __KERNEL_DS */ + .quad GDT_ENTRY(0x4090, 0, 0x18) /* PVH_CANARY_SEL */ gdt_end: - .balign 4 + .balign 16 +canary: + .fill 48, 1, 0 + early_stack: .fill 256, 1, 0 early_stack_end: