From patchwork Thu Apr 16 13:21:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 227697 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 36B97C352BE for ; Thu, 16 Apr 2020 15:05:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 14C7B214AF for ; Thu, 16 Apr 2020 15:05:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587049500; bh=iFWKPM79D+eOwWhbxjk4po4LTD20a1ZJmbOg1VrHgQg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=N/KW3zKRMIMxBj3S8vmJIj0pyEbVeQiNBrPtQF+KvJ+FM766XPEpk0X5DC3hnvXzS ZY+M+U8SnMKNMA8dxixmvkNHY4oeaUNys4kxVl6+BunN+CgWO3zCDk+jbwhg4X85Gq 6Kk1RYtrIVWh72Z2fuyF8hr+sscD/m1ArtUjFYvQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2408913AbgDPNw4 (ORCPT ); Thu, 16 Apr 2020 09:52:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:39250 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2408903AbgDPNwy (ORCPT ); Thu, 16 Apr 2020 09:52:54 -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 122DF20732; Thu, 16 Apr 2020 13:52:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587045173; bh=iFWKPM79D+eOwWhbxjk4po4LTD20a1ZJmbOg1VrHgQg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=owWeskQ1LAn+MvSjW0qAgf5Ib0SkmV0z+M+8Jt0zMplFB7m3sNc7MxmXzMkKbVoxO Xh0sPstVNOy2HUzyT2n4eLAQv1artACFRK6Ip4d2XaJIg3RjLJp8cKbqzN9Fey/0qq PHhSImlOQf+DBbjZNUV4fsqMZO5mECjfY3EmTZxM= 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 5.6 027/254] x86: Dont let pgprot_modify() change the page encryption bit Date: Thu, 16 Apr 2020 15:21:56 +0200 Message-Id: <20200416131329.230384350@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200416131325.804095985@linuxfoundation.org> References: <20200416131325.804095985@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 7e118660bbd98..64a03f226ab73 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -627,12 +627,15 @@ 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 0239998d8cdc0..65c2ecd730c5b 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -118,7 +118,7 @@ */ #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) /*