From patchwork Thu Apr 16 13:22:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 227511 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=unavailable 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 06F1CC2BB85 for ; Thu, 16 Apr 2020 16:02:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DB96F217D8 for ; Thu, 16 Apr 2020 16:02:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587052946; bh=vSXvfk+ZBHDHOnvNignHEMR/sPicw9FxaumxDke6jfU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SPHJaEayvvC96n4gLJRkMS8mytqJK/6rwrH3Ph35KdSF9KOMojtICRgTearse6Bqy uEamipgpCgch/JUnlnn29i8XJ4Kea6UFmC4u1MsT5M09MsMclfrrvRW/7IjhS4/4nx WQVTN3Co8/vbmsmfLfZbdoxDKttX544huZeNN7CI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2895285AbgDPN0k (ORCPT ); Thu, 16 Apr 2020 09:26:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:34390 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2895058AbgDPN0f (ORCPT ); Thu, 16 Apr 2020 09:26:35 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 5833721D93; Thu, 16 Apr 2020 13:26:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587043583; bh=vSXvfk+ZBHDHOnvNignHEMR/sPicw9FxaumxDke6jfU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fcu6aw9hc6BN+R3G6bruTPPt4BRwhoqanwtT5wXr651Bf2flkpugHlCHkDjmSS8jx RyGNnq6t9wBIHHJdWgBph8908Ld+0ZpRDw/MMUdV/kD8WWkBgdGGj+SB3fg/LXUXhq 3jRjRJ2+RJGKOJrFz1CHSImUnn6TSnCAt8kScg2Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Hellstrom , Borislav Petkov , Dave Hansen , Tom Lendacky , Sasha Levin Subject: [PATCH 4.19 017/146] x86: Dont let pgprot_modify() change the page encryption bit Date: Thu, 16 Apr 2020 15:22:38 +0200 Message-Id: <20200416131244.884838189@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200416131242.353444678@linuxfoundation.org> References: <20200416131242.353444678@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Thomas Hellstrom [ Upstream commit 6db73f17c5f155dbcfd5e48e621c706270b84df0 ] When SEV or SME is enabled and active, vm_get_page_prot() typically returns with the encryption bit set. This means that users of pgprot_modify(, vm_get_page_prot()) (mprotect_fixup(), do_mmap()) end up with a value of vma->vm_pg_prot that is not consistent with the intended protection of the PTEs. This is also important for fault handlers that rely on the VMA vm_page_prot to set the page protection. Fix this by not allowing pgprot_modify() to change the encryption bit, similar to how it's done for PAT bits. Signed-off-by: Thomas Hellstrom Signed-off-by: Borislav Petkov Reviewed-by: Dave Hansen Acked-by: Tom Lendacky Link: https://lkml.kernel.org/r/20200304114527.3636-2-thomas_os@shipmail.org Signed-off-by: Sasha Levin --- arch/x86/include/asm/pgtable.h | 7 +++++-- arch/x86/include/asm/pgtable_types.h | 2 +- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 690c0307afed0..2e1ed12c65f82 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -608,12 +608,15 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) return __pmd(val); } -/* mprotect needs to preserve PAT bits when updating vm_page_prot */ +/* + * mprotect needs to preserve PAT and encryption bits when updating + * vm_page_prot + */ #define pgprot_modify pgprot_modify static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) { pgprotval_t preservebits = pgprot_val(oldprot) & _PAGE_CHG_MASK; - pgprotval_t addbits = pgprot_val(newprot); + pgprotval_t addbits = pgprot_val(newprot) & ~_PAGE_CHG_MASK; return __pgprot(preservebits | addbits); } diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 106b7d0e2dae5..71ea49e7db747 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -124,7 +124,7 @@ */ #define _PAGE_CHG_MASK (PTE_PFN_MASK | _PAGE_PCD | _PAGE_PWT | \ _PAGE_SPECIAL | _PAGE_ACCESSED | _PAGE_DIRTY | \ - _PAGE_SOFT_DIRTY | _PAGE_DEVMAP) + _PAGE_SOFT_DIRTY | _PAGE_DEVMAP | _PAGE_ENC) #define _HPAGE_CHG_MASK (_PAGE_CHG_MASK | _PAGE_PSE) /*