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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 99903C43441 for ; Mon, 19 Nov 2018 03:49:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5B46D20817 for ; Mon, 19 Nov 2018 03:49:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5B46D20817 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=1wt.eu 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 S1728166AbeKSOLg (ORCPT ); Mon, 19 Nov 2018 09:11:36 -0500 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:45042 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726903AbeKSOLg (ORCPT ); Mon, 19 Nov 2018 09:11:36 -0500 Received: (from willy@localhost) by pcw.home.local (8.15.2/8.15.2/Submit) id wAJ3mkTk011411; Mon, 19 Nov 2018 04:48:46 +0100 Date: Mon, 19 Nov 2018 04:48:46 +0100 From: Willy Tarreau To: Tim Chen Cc: Jiri Kosina , Linus Torvalds , Thomas Gleixner , Peter Zijlstra , Josh Poimboeuf , Andrea Arcangeli , David Woodhouse , Andi Kleen , Casey Schaufler , Linux List Kernel Mailing , the arch/x86 maintainers , stable@vger.kernel.org Subject: Re: STIBP by default.. Revert? Message-ID: <20181119034846.GA11333@1wt.eu> References: <32d00fb2-7187-ed6f-ab1e-287151e82b3a@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <32d00fb2-7187-ed6f-ab1e-287151e82b3a@linux.intel.com> User-Agent: Mutt/1.6.1 (2016-04-27) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Nov 18, 2018 at 02:40:28PM -0800, Tim Chen wrote: > Tasks that want extra security will enable that via prctl interface or > making themselves non-dumpable. Well, you need to be careful regarding the last part of your option above, because a number of network daemons become non-dumpable by executing setuid() at boot, and certainly don't want to suffer a performance loss as a side effect of wanting to become "normally" secure. I'd suggest to use the prctl only so that it doesn't randomly hit innocent applications that would only have as a last resort to turn off reasonable security features to avoid this impact. Regards, Willy