From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 6400A7D085 for ; Tue, 10 Jul 2018 22:33:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732705AbeGJWeP (ORCPT ); Tue, 10 Jul 2018 18:34:15 -0400 Received: from mga12.intel.com ([192.55.52.136]:33776 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732385AbeGJWcY (ORCPT ); Tue, 10 Jul 2018 18:32:24 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Jul 2018 15:31:14 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,335,1526367600"; d="scan'208";a="70305420" Received: from 2b52.sc.intel.com ([143.183.136.52]) by fmsmga004.fm.intel.com with ESMTP; 10 Jul 2018 15:31:14 -0700 From: Yu-cheng Yu To: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Cyrill Gorcunov , Dave Hansen , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , "Ravi V. Shankar" , Vedvyas Shanbhogue Cc: Yu-cheng Yu Subject: [RFC PATCH v2 15/27] mm/mprotect: Prevent mprotect from changing shadow stack Date: Tue, 10 Jul 2018 15:26:27 -0700 Message-Id: <20180710222639.8241-16-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180710222639.8241-1-yu-cheng.yu@intel.com> References: <20180710222639.8241-1-yu-cheng.yu@intel.com> Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Signed-off-by: Yu-cheng Yu --- mm/mprotect.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/mprotect.c b/mm/mprotect.c index 625608bc8962..128dcb880c12 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -446,6 +446,15 @@ static int do_mprotect_pkey(unsigned long start, size_t len, error = -ENOMEM; if (!vma) goto out; + + /* + * Do not allow changing shadow stack memory. + */ + if (vma->vm_flags & VM_SHSTK) { + error = -EINVAL; + goto out; + } + prev = vma->vm_prev; if (unlikely(grows & PROT_GROWSDOWN)) { if (vma->vm_start >= end) -- 2.17.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html