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=-3.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 4EDF2C43387 for ; Sat, 22 Dec 2018 23:08:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 23E2F206A3 for ; Sat, 22 Dec 2018 23:08:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404342AbeLVXIo (ORCPT ); Sat, 22 Dec 2018 18:08:44 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:40498 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731156AbeLVXIn (ORCPT ); Sat, 22 Dec 2018 18:08:43 -0500 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::cf9]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 26E4F14A8F325; Sat, 22 Dec 2018 15:08:43 -0800 (PST) Date: Sat, 22 Dec 2018 15:08:42 -0800 (PST) Message-Id: <20181222.150842.1563344934152542563.davem@davemloft.net> To: gustavo@embeddedor.com Cc: courmisch@gmail.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] phonet: af_phonet: Fix Spectre v1 vulnerability From: David Miller In-Reply-To: <20181221214117.GA1539@embeddedor> References: <20181221214117.GA1539@embeddedor> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sat, 22 Dec 2018 15:08:43 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Gustavo A. R. Silva" Date: Fri, 21 Dec 2018 15:41:17 -0600 > protocol is indirectly controlled by user-space, hence leading to > a potential exploitation of the Spectre variant 1 vulnerability. > > This issue was detected with the help of Smatch: > > net/phonet/af_phonet.c:48 phonet_proto_get() warn: potential spectre issue 'proto_tab' [w] (local cap) > > Fix this by sanitizing protocol before using it to index proto_tab. > > Notice that given that speculation windows are large, the policy is > to kill the speculation on the first load and not worry if it can be > completed with a dependent load/store [1]. > > [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 > > Signed-off-by: Gustavo A. R. Silva Applied, thanks.