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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 8438EC433E0 for ; Thu, 4 Jun 2020 15:03:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E11B207D8 for ; Thu, 4 Jun 2020 15:03:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729193AbgFDPDk (ORCPT ); Thu, 4 Jun 2020 11:03:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58766 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728638AbgFDPDi (ORCPT ); Thu, 4 Jun 2020 11:03:38 -0400 Received: from ZenIV.linux.org.uk (zeniv.linux.org.uk [IPv6:2002:c35c:fd02::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B0EEC08C5C0; Thu, 4 Jun 2020 08:03:38 -0700 (PDT) Received: from viro by ZenIV.linux.org.uk with local (Exim 4.93 #3 (Red Hat Linux)) id 1jgrP5-0033lc-U6; Thu, 04 Jun 2020 15:03:35 +0000 Date: Thu, 4 Jun 2020 16:03:35 +0100 From: Al Viro To: "Michael S. Tsirkin" Cc: linux-kernel@vger.kernel.org, Jason Wang , netdev@vger.kernel.org Subject: Re: [PATCH RFC] uaccess: user_access_begin_after_access_ok() Message-ID: <20200604150335.GG23230@ZenIV.linux.org.uk> References: <20200602084257.134555-1-mst@redhat.com> <20200603014815.GR23230@ZenIV.linux.org.uk> <20200603011810-mutt-send-email-mst@kernel.org> <20200603165205.GU23230@ZenIV.linux.org.uk> <20200604054516-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200604054516-mutt-send-email-mst@kernel.org> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Jun 04, 2020 at 06:10:23AM -0400, Michael S. Tsirkin wrote: > stac() > for (i = 0; i < 64; ++i) { > get_user(flags, desc[i].flags) unsafe_get_user(), please. > smp_rmb() > if (!(flags & VALID)) > break; > copy_from_user(&adesc[i], desc + i, sizeof adesc[i]); ... and that would raw_copy_from_user() (or unsafe_copy_from_user(), for wrapper that would take a label to bugger off to) > } > clac()