From patchwork Tue Dec 4 07:39:49 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alison Schofield X-Patchwork-Id: 10711187 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A0DA216B1 for ; Tue, 4 Dec 2018 07:37:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7CB802A506 for ; Tue, 4 Dec 2018 07:37:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6DC9A2A57C; Tue, 4 Dec 2018 07:37:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0E4332A506 for ; Tue, 4 Dec 2018 07:37:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725983AbeLDHhZ (ORCPT ); Tue, 4 Dec 2018 02:37:25 -0500 Received: from mga03.intel.com ([134.134.136.65]:5832 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725994AbeLDHhY (ORCPT ); Tue, 4 Dec 2018 02:37:24 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Dec 2018 23:37:24 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,313,1539673200"; d="scan'208";a="98463926" Received: from alison-desk.jf.intel.com (HELO alison-desk) ([10.54.74.53]) by orsmga008.jf.intel.com with ESMTP; 03 Dec 2018 23:37:22 -0800 From: Alison Schofield To: dhowells@redhat.com, tglx@linutronix.de Cc: jmorris@namei.org, mingo@redhat.com, hpa@zytor.com, bp@alien8.de, luto@kernel.org, peterz@infradead.org, kirill.shutemov@linux.intel.com, dave.hansen@intel.com, kai.huang@intel.com, jun.nakajima@intel.com, dan.j.williams@intel.com, jarkko.sakkinen@intel.com, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org Subject: [RFC v2 02/13] mm: Generalize the mprotect implementation to support extensions Date: Mon, 3 Dec 2018 23:39:49 -0800 Message-Id: <3389bc8e46479ba102f88c157aebd49b905ac289.1543903910.git.alison.schofield@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Today mprotect is implemented to support legacy mprotect behavior plus an extension for memory protection keys. Make it more generic so that it can support additional extensions in the future. This is done is preparation for adding a new system call for memory encyption keys. The intent is that the new encrypted mprotect will be another extension to legacy mprotect. Change-Id: Ib09b9d1b605b12d0254d7fb4968dfcc8e3c79dd7 Signed-off-by: Alison Schofield Signed-off-by: Kirill A. Shutemov --- mm/mprotect.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/mm/mprotect.c b/mm/mprotect.c index df408956dccc..b57075e278fb 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -35,6 +35,8 @@ #include "internal.h" +#define NO_KEY -1 + static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t newprot, int dirty_accountable, int prot_numa) @@ -451,9 +453,9 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev, } /* - * pkey==-1 when doing a legacy mprotect() + * When pkey==NO_KEY we get legacy mprotect behavior here. */ -static int do_mprotect_pkey(unsigned long start, size_t len, +static int do_mprotect_ext(unsigned long start, size_t len, unsigned long prot, int pkey) { unsigned long nstart, end, tmp, reqprot; @@ -577,7 +579,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len, SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len, unsigned long, prot) { - return do_mprotect_pkey(start, len, prot, -1); + return do_mprotect_ext(start, len, prot, NO_KEY); } #ifdef CONFIG_ARCH_HAS_PKEYS @@ -585,7 +587,7 @@ SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len, SYSCALL_DEFINE4(pkey_mprotect, unsigned long, start, size_t, len, unsigned long, prot, int, pkey) { - return do_mprotect_pkey(start, len, prot, pkey); + return do_mprotect_ext(start, len, prot, pkey); } SYSCALL_DEFINE2(pkey_alloc, unsigned long, flags, unsigned long, init_val)