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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 35FB6C677E4 for ; Mon, 8 Oct 2018 18:46:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 004DA2064A for ; Mon, 8 Oct 2018 18:46:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="rc90iIFJ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 004DA2064A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org 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 S1731158AbeJIB7O (ORCPT ); Mon, 8 Oct 2018 21:59:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:47440 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728570AbeJIB7N (ORCPT ); Mon, 8 Oct 2018 21:59:13 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EE7722064A; Mon, 8 Oct 2018 18:46:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539024367; bh=CNQqPVLaAzNc/y6r86HbUERgvUq8uQm94vmTnjZhs2Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rc90iIFJbj+dtGwKnH+gbpjKeVvZGB7gKrJWuQowz+pFOiBcY0zYnNHcuemk9xGMP +VbMU6Ee5WvIwZfhoZN0OaXU+9B38i+ZPBxl9baTfGCSUL0yoOLEe7iSQMnnquDSXV RCiDSfeTA0i/hmiqYrkpiwLMcvmUrtzC5GiattCg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jinbum Park , Johannes Berg , Sasha Levin Subject: [PATCH 4.18 018/168] mac80211_hwsim: Fix possible Spectre-v1 for hwsim_world_regdom_custom Date: Mon, 8 Oct 2018 20:29:58 +0200 Message-Id: <20181008175620.744522583@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181008175620.043587728@linuxfoundation.org> References: <20181008175620.043587728@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jinbum Park [ Upstream commit 3a2af7cccbbaf2362db9053a946a6084e12bfa73 ] User controls @idx which to be used as index of hwsim_world_regdom_custom. So, It can be exploited via Spectre-like attack. (speculative execution) This kind of attack leaks address of hwsim_world_regdom_custom, It leads an attacker to bypass security mechanism such as KASLR. So sanitize @idx before using it to prevent attack. I leveraged strategy [1] to find and exploit this gadget. [1] https://github.com/jinb-park/linux-exploit/tree/master/exploit-remaining-spectre-gadget/ Signed-off-by: Jinbum Park [johannes: unwrap URL] Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/mac80211_hwsim.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/net/wireless/mac80211_hwsim.c +++ b/drivers/net/wireless/mac80211_hwsim.c @@ -33,6 +33,7 @@ #include #include #include +#include #include "mac80211_hwsim.h" #define WARN_QUEUE 100 @@ -3229,6 +3230,9 @@ static int hwsim_new_radio_nl(struct sk_ kfree(hwname); return -EINVAL; } + + idx = array_index_nospec(idx, + ARRAY_SIZE(hwsim_world_regdom_custom)); param.regd = hwsim_world_regdom_custom[idx]; }