From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 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> Sender: stable-owner@vger.kernel.org List-ID: 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