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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,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 5135EC433E0 for ; Wed, 27 May 2020 21:18:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 30037207E8 for ; Wed, 27 May 2020 21:18:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728571AbgE0VSa (ORCPT ); Wed, 27 May 2020 17:18:30 -0400 Received: from foss.arm.com ([217.140.110.172]:44778 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726114AbgE0VS3 (ORCPT ); Wed, 27 May 2020 17:18:29 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A056CD6E; Wed, 27 May 2020 14:18:28 -0700 (PDT) Received: from e103592.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A38323F52E; Wed, 27 May 2020 14:18:27 -0700 (PDT) From: Dave Martin To: Michael Kerrisk Cc: linux-man@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Waiman Long , Thomas Gleixner Subject: [PATCH v2 3/6] prctl.2: Add PR_SPEC_DISABLE_NOEXEC for SPECULATION_CTRL prctls Date: Wed, 27 May 2020 22:17:35 +0100 Message-Id: <1590614258-24728-4-git-send-email-Dave.Martin@arm.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1590614258-24728-1-git-send-email-Dave.Martin@arm.com> References: <1590614258-24728-1-git-send-email-Dave.Martin@arm.com> Sender: linux-man-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-man@vger.kernel.org Add the PR_SPEC_DISABLE_NOEXEC mode added in Linux 5.1 for the PR_SPEC_STORE_BYPASS "misfeature" of PR_SET_SPECULATION_CTRL and PR_GET_SPECULATION_CTRL. Signed-off-by: Dave Martin Cc: Waiman Long Cc: Thomas Gleixner --- man2/prctl.2 | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/man2/prctl.2 b/man2/prctl.2 index b6fb51c..cab9915 100644 --- a/man2/prctl.2 +++ b/man2/prctl.2 @@ -1187,6 +1187,12 @@ The speculation feature is disabled, mitigation is enabled. Same as .B PR_SPEC_DISABLE but cannot be undone. +.TP +.BR PR_SPEC_DISABLE_NOEXEC " (since Linux 5.1)" +Same as +.BR PR_SPEC_DISABLE , +but but the state will be cleared on +.BR execve (2). .RE .IP If all bits are 0, @@ -1251,6 +1257,17 @@ with the same value for .I arg2 will fail with the error .BR EPERM . +.\" commit 71368af9027f18fe5d1c6f372cfdff7e4bde8b48 +.TP +.BR PR_SPEC_DISABLE_NOEXEC " (since Linux 5.1)" +Same as +.BR PR_SPEC_DISABLE , +but but the state will be cleared on +.BR execve (2). +Currently only supported for +.I arg2 +equal to +.B PR_SPEC_STORE_BYPASS. .RE .IP Any unsupported value in @@ -1899,11 +1916,12 @@ was .BR PR_SET_SPECULATION_CTRL and .IR arg3 -is neither +is not .BR PR_SPEC_ENABLE , .BR PR_SPEC_DISABLE , +.BR PR_SPEC_FORCE_DISABLE , nor -.BR PR_SPEC_FORCE_DISABLE . +.BR PR_SPEC_DISABLE_NOEXEC . .SH VERSIONS The .BR prctl () -- 2.1.4