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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 4B981C10F13 for ; Thu, 11 Apr 2019 11:46:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 215C72184B for ; Thu, 11 Apr 2019 11:46:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726786AbfDKLqy (ORCPT ); Thu, 11 Apr 2019 07:46:54 -0400 Received: from ozlabs.org ([203.11.71.1]:52127 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726629AbfDKLqy (ORCPT ); Thu, 11 Apr 2019 07:46:54 -0400 Received: by ozlabs.org (Postfix, from userid 1034) id 44fzlJ1FfVz9sCF; Thu, 11 Apr 2019 21:46:52 +1000 (AEST) From: Michael Ellerman To: stable@vger.kernel.org, gregkh@linuxfoundation.org Cc: linuxppc-dev@ozlabs.org, diana.craciun@nxp.com, msuchanek@suse.de, christophe.leroy@c-s.fr Subject: [PATCH stable v4.9 10/35] powerpc64s: Show ori31 availability in spectre_v1 sysfs file not v2 Date: Thu, 11 Apr 2019 21:46:05 +1000 Message-Id: <20190411114630.4042-11-mpe@ellerman.id.au> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190411114630.4042-1-mpe@ellerman.id.au> References: <20190411114630.4042-1-mpe@ellerman.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org commit 6d44acae1937b81cf8115ada8958e04f601f3f2e upstream. When I added the spectre_v2 information in sysfs, I included the availability of the ori31 speculation barrier. Although the ori31 barrier can be used to mitigate v2, it's primarily intended as a spectre v1 mitigation. Spectre v2 is mitigated by hardware changes. So rework the sysfs files to show the ori31 information in the spectre_v1 file, rather than v2. Currently we display eg: $ grep . spectre_v* spectre_v1:Mitigation: __user pointer sanitization spectre_v2:Mitigation: Indirect branch cache disabled, ori31 speculation barrier enabled After: $ grep . spectre_v* spectre_v1:Mitigation: __user pointer sanitization, ori31 speculation barrier enabled spectre_v2:Mitigation: Indirect branch cache disabled Fixes: d6fbe1c55c55 ("powerpc/64s: Wire up cpu_show_spectre_v2()") Cc: stable@vger.kernel.org # v4.17+ Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/security.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c index f189f946d935..bf298d0c475f 100644 --- a/arch/powerpc/kernel/security.c +++ b/arch/powerpc/kernel/security.c @@ -118,25 +118,35 @@ ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, cha ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf) { - if (!security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR)) - return sprintf(buf, "Not affected\n"); + struct seq_buf s; + + seq_buf_init(&s, buf, PAGE_SIZE - 1); - if (barrier_nospec_enabled) - return sprintf(buf, "Mitigation: __user pointer sanitization\n"); + if (security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR)) { + if (barrier_nospec_enabled) + seq_buf_printf(&s, "Mitigation: __user pointer sanitization"); + else + seq_buf_printf(&s, "Vulnerable"); - return sprintf(buf, "Vulnerable\n"); + if (security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31)) + seq_buf_printf(&s, ", ori31 speculation barrier enabled"); + + seq_buf_printf(&s, "\n"); + } else + seq_buf_printf(&s, "Not affected\n"); + + return s.len; } ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf) { - bool bcs, ccd, ori; struct seq_buf s; + bool bcs, ccd; seq_buf_init(&s, buf, PAGE_SIZE - 1); bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED); ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED); - ori = security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31); if (bcs || ccd) { seq_buf_printf(&s, "Mitigation: "); @@ -152,9 +162,6 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, c } else seq_buf_printf(&s, "Vulnerable"); - if (ori) - seq_buf_printf(&s, ", ori31 speculation barrier enabled"); - seq_buf_printf(&s, "\n"); return s.len; -- 2.20.1