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=-13.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 C8535C43444 for ; Tue, 8 Jan 2019 20:04:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 966D920827 for ; Tue, 8 Jan 2019 20:04:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546977862; bh=V4xGP7AvQceKMyoNwU1chVCiS2JZFGNHAF3N1QNWmWY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=obzzlBheMVKr+pn+6VEl+JqrENUJm09xui+xiK0j7KZ5GwmLe4DvceXqo+N5r35XN jkNrxK6r2m3Sfad4KMF5N6mDDMkQPaUcRPC7zRLTyi+ALMUbg2wMM0GBoux+V6wQqC ozYGgWw9d+vGIAGp2d/Cd2Gag5BNg7sZueZT4gQ0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730076AbfAHT2d (ORCPT ); Tue, 8 Jan 2019 14:28:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:35464 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730025AbfAHT20 (ORCPT ); Tue, 8 Jan 2019 14:28:26 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E5D7220883; Tue, 8 Jan 2019 19:28:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546975705; bh=V4xGP7AvQceKMyoNwU1chVCiS2JZFGNHAF3N1QNWmWY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=beJvIWWYFN1ZPzPG5mu5f8GhagaTkXE0O0tXyObtvvey8jTf7S/ftiAhOQUNnOJgm ITyzT9lPkJ+UKI7DFtcN25taPt+l6HdSbstmlP75syKyK3NqEaLYirMYnhGPrJBfDC yiLly917iYdV8672IvuU+52/ifrE1NqJJhpSvuxM= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Reinette Chatre , Borislav Petkov , "H. Peter Anvin" , Ingo Molnar , Thomas Gleixner , Tony Luck , fenghua.yu@intel.com, gavin.hindman@intel.com, jithu.joseph@intel.com, x86-ml , Sasha Levin Subject: [PATCH AUTOSEL 4.20 066/117] x86/resctrl: Fix rdt_find_domain() return value and checks Date: Tue, 8 Jan 2019 14:25:34 -0500 Message-Id: <20190108192628.121270-66-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190108192628.121270-1-sashal@kernel.org> References: <20190108192628.121270-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Reinette Chatre [ Upstream commit 52eb74339a6233c69f4e3794b69ea7c98eeeae1b ] 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 Signed-off-by: Sasha Levin --- arch/x86/kernel/cpu/intel_rdt.c | 2 +- arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c | 2 +- arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c index 44272b7107ad..2d0a565fd0bb 100644 --- a/arch/x86/kernel/cpu/intel_rdt.c +++ b/arch/x86/kernel/cpu/intel_rdt.c @@ -421,7 +421,7 @@ 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/intel_rdt_ctrlmondata.c b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c index efa4a519f5e5..c8b72aff55e0 100644 --- a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c +++ b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c @@ -467,7 +467,7 @@ 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/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c index f27b8115ffa2..951c61367688 100644 --- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c +++ b/arch/x86/kernel/cpu/intel_rdt_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; } -- 2.19.1