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=-11.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS 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 ABA08C6783B for ; Tue, 11 Dec 2018 21:16:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6E3A42086D for ; Tue, 11 Dec 2018 21:16:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6E3A42086D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zytor.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726283AbeLKVQI (ORCPT ); Tue, 11 Dec 2018 16:16:08 -0500 Received: from terminus.zytor.com ([198.137.202.136]:33273 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726134AbeLKVQH (ORCPT ); Tue, 11 Dec 2018 16:16:07 -0500 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id wBBLFvHJ4154914 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 11 Dec 2018 13:15:57 -0800 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id wBBLFvAZ4154911; Tue, 11 Dec 2018 13:15:57 -0800 Date: Tue, 11 Dec 2018 13:15:57 -0800 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Reinette Chatre Message-ID: Cc: bp@suse.de, tony.luck@intel.com, reinette.chatre@intel.com, hpa@zytor.com, mingo@kernel.org, x86@kernel.org, mingo@redhat.com, linux-kernel@vger.kernel.org, tglx@linutronix.de Reply-To: reinette.chatre@intel.com, bp@suse.de, tony.luck@intel.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, mingo@redhat.com, hpa@zytor.com, mingo@kernel.org, x86@kernel.org In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/cache] x86/resctrl: Fix rdt_find_domain() return value and checks Git-Commit-ID: 52eb74339a6233c69f4e3794b69ea7c98eeeae1b X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 52eb74339a6233c69f4e3794b69ea7c98eeeae1b Gitweb: https://git.kernel.org/tip/52eb74339a6233c69f4e3794b69ea7c98eeeae1b Author: Reinette Chatre AuthorDate: Mon, 10 Dec 2018 14:31:13 -0800 Committer: Borislav Petkov CommitDate: Tue, 11 Dec 2018 22:09:28 +0100 x86/resctrl: Fix rdt_find_domain() return value and checks rdt_find_domain() returns an ERR_PTR() that is generated from a provided domain id when the value is negative. Care needs to be taken when creating an ERR_PTR() from this value because a subsequent check using IS_ERR() expects the error to be within the MAX_ERRNO range. Using an invalid domain id as an ERR_PTR() does work at this time since this is currently always -1. Using this undocumented assumption is fragile since future users of rdt_find_domain() may not be aware of thus assumption. Two related issues are addressed: - Ensure that rdt_find_domain() always returns a valid error value by forcing the error to be -ENODEV when a negative domain id is provided. - In a few instances the return value of rdt_find_domain() is just checked for NULL - fix these to include a check of ERR_PTR. Fixes: d89b7379015f ("x86/intel_rdt/cqm: Add mon_data") Fixes: 521348b011d6 ("x86/intel_rdt: Introduce utility to obtain CDP peer") Signed-off-by: Reinette Chatre Signed-off-by: Borislav Petkov Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Tony Luck Cc: fenghua.yu@intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: x86-ml Link: https://lkml.kernel.org/r/b88cd4ff6a75995bf8db9b0ea546908fe50f69f3.1544479852.git.reinette.chatre@intel.com --- arch/x86/kernel/cpu/resctrl/core.c | 2 +- arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 2 +- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index 2ec252be4ed9..c3a9dc63edf2 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -454,7 +454,7 @@ struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id, struct list_head *l; if (id < 0) - return ERR_PTR(id); + return ERR_PTR(-ENODEV); list_for_each(l, &r->domains) { d = list_entry(l, struct rdt_domain, list); diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c index ba11f54f5ab8..3b943ace786c 100644 --- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c +++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c @@ -534,7 +534,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg) r = &rdt_resources_all[resid]; d = rdt_find_domain(r, domid, NULL); - if (!d) { + if (IS_ERR_OR_NULL(d)) { ret = -ENOENT; goto out; } diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 017505017bdb..8388adf241b2 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -1029,7 +1029,7 @@ static int rdt_cdp_peer_get(struct rdt_resource *r, struct rdt_domain *d, * peer RDT CDP resource. Hence the WARN. */ _d_cdp = rdt_find_domain(_r_cdp, d->id, NULL); - if (WARN_ON(!_d_cdp)) { + if (WARN_ON(IS_ERR_OR_NULL(_d_cdp))) { _r_cdp = NULL; ret = -EINVAL; }