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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 D6C7DC43381 for ; Mon, 11 Mar 2019 19:56:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9CE38214D8 for ; Mon, 11 Mar 2019 19:56:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552334181; bh=1qc6AvIxnwuXD9TmCLZFwLIcNpe3n/znD6Nwl5bj13A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1oGg5vCFTG1f1PPwUkv6P++7ubO1KJuPMDbWJkMgRTVTZokwAaWB0qHHqzD5jYvJ9 KBc+e9c3vB/YW9NsF0+wxq0LFcwfuD9sHwey7nXgqVCvdHsJBtQDQuDnSi3nnZIvnc wuiDa3R2YM+1N72nmnlD0w3LhtjDfYJkxsK3ZPNA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728623AbfCKT4T (ORCPT ); Mon, 11 Mar 2019 15:56:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:33422 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728555AbfCKT4M (ORCPT ); Mon, 11 Mar 2019 15:56:12 -0400 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 203D62087C; Mon, 11 Mar 2019 19:56:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552334171; bh=1qc6AvIxnwuXD9TmCLZFwLIcNpe3n/znD6Nwl5bj13A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mZXGNE3eSh3TjN1bGFmC2N7GFogo9tjPfKkBxdP5o0XhQLAB13x5Yn6/brvXArMKY qPM53KQtHkVVGcG5TqyY/Qe/8AMXRsar2rXobw/zeHAWj2aeKD3pFo1K4jZnwH2n/c CdUwEzqA2osAqklJokgaOb0SiYUsORNaJgIBp/gw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Johannes Berg , Luca Coelho , Sasha Levin , linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.20 29/52] cfg80211: prevent speculation on cfg80211_classify8021d() return Date: Mon, 11 Mar 2019 15:54:53 -0400 Message-Id: <20190311195516.137772-29-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190311195516.137772-1-sashal@kernel.org> References: <20190311195516.137772-1-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: Johannes Berg [ Upstream commit 1fc9b7253382ce1a83d9a3e63e88d656eb63f263 ] It's possible that the caller of cfg80211_classify8021d() uses the value to index an array, like mac80211 in ieee80211_downgrade_queue(). Prevent speculation on the return value. Signed-off-by: Johannes Berg Signed-off-by: Luca Coelho Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/wireless/util.c | 35 ++++++++++++++++++++++++----------- 1 file changed, 24 insertions(+), 11 deletions(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index d473bd135da8..d8b7eb75bade 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -5,7 +5,7 @@ * Copyright 2007-2009 Johannes Berg * Copyright 2013-2014 Intel Mobile Communications GmbH * Copyright 2017 Intel Deutschland GmbH - * Copyright (C) 2018 Intel Corporation + * Copyright (C) 2018-2019 Intel Corporation */ #include #include @@ -19,6 +19,7 @@ #include #include #include +#include #include "core.h" #include "rdev-ops.h" @@ -715,20 +716,25 @@ unsigned int cfg80211_classify8021d(struct sk_buff *skb, { unsigned int dscp; unsigned char vlan_priority; + unsigned int ret; /* skb->priority values from 256->263 are magic values to * directly indicate a specific 802.1d priority. This is used * to allow 802.1d priority to be passed directly in from VLAN * tags, etc. */ - if (skb->priority >= 256 && skb->priority <= 263) - return skb->priority - 256; + if (skb->priority >= 256 && skb->priority <= 263) { + ret = skb->priority - 256; + goto out; + } if (skb_vlan_tag_present(skb)) { vlan_priority = (skb_vlan_tag_get(skb) & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT; - if (vlan_priority > 0) - return vlan_priority; + if (vlan_priority > 0) { + ret = vlan_priority; + goto out; + } } switch (skb->protocol) { @@ -747,8 +753,9 @@ unsigned int cfg80211_classify8021d(struct sk_buff *skb, if (!mpls) return 0; - return (ntohl(mpls->entry) & MPLS_LS_TC_MASK) + ret = (ntohl(mpls->entry) & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT; + goto out; } case htons(ETH_P_80221): /* 802.21 is always network control traffic */ @@ -761,18 +768,24 @@ unsigned int cfg80211_classify8021d(struct sk_buff *skb, unsigned int i, tmp_dscp = dscp >> 2; for (i = 0; i < qos_map->num_des; i++) { - if (tmp_dscp == qos_map->dscp_exception[i].dscp) - return qos_map->dscp_exception[i].up; + if (tmp_dscp == qos_map->dscp_exception[i].dscp) { + ret = qos_map->dscp_exception[i].up; + goto out; + } } for (i = 0; i < 8; i++) { if (tmp_dscp >= qos_map->up[i].low && - tmp_dscp <= qos_map->up[i].high) - return i; + tmp_dscp <= qos_map->up[i].high) { + ret = i; + goto out; + } } } - return dscp >> 5; + ret = dscp >> 5; +out: + return array_index_nospec(ret, IEEE80211_NUM_TIDS); } EXPORT_SYMBOL(cfg80211_classify8021d); -- 2.19.1