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=-1.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 422A9C00319 for ; Thu, 21 Feb 2019 07:37:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11F9B214AF for ; Thu, 21 Feb 2019 07:37:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550734653; bh=3boNodBwnnXjiRO2V2TYP+SfUuWKf/IfOym8qlKkqm0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=ZAn4RqXk2g3nAtMe12UF3rAT0Vh01iEJ/+bvF1+XhSV+yuRYHvRZ1LfP49dh5fRSZ WypmrRJKu92i/MlrVexubNOwWRIDiarnd37CiMhHXQHPw8kmRtsmujtGqUahfP/AhW 11Kaa65/HQtmCyhAEXkWgvaD8kzolEuhboMman3A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726729AbfBUHhb (ORCPT ); Thu, 21 Feb 2019 02:37:31 -0500 Received: from mail.kernel.org ([198.145.29.99]:40948 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725648AbfBUHhb (ORCPT ); Thu, 21 Feb 2019 02:37:31 -0500 Received: from devbox (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (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 A10222147A; Thu, 21 Feb 2019 07:37:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550734650; bh=3boNodBwnnXjiRO2V2TYP+SfUuWKf/IfOym8qlKkqm0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=v2NhBi/1s0+f6+cusVWhpHxTlvjkZR/KkkPjAA784gJh+Gp6Zd13nHqFifNp88yTr +2maNlmxtxDPGP3RHshzXvOQSWj+QV6mHjebQ6IJlBVjAEp1eo798kYWS292Fh7nCP FQk6jUgBh8GFcArHFiPWliDw9rTjtF99g/Fd51Po= Date: Thu, 21 Feb 2019 16:37:26 +0900 From: Masami Hiramatsu To: Steven Rostedt Cc: Linus Torvalds , Andy Lutomirski , Linux List Kernel Mailing , Ingo Molnar , Andrew Morton , stable , Changbin Du , Jann Horn , Kees Cook , Andy Lutomirski Subject: Re: [PATCH 1/2 v2] kprobe: Do not use uaccess functions to access kernel memory that can fault Message-Id: <20190221163726.9f4db72bd38be953b74419eb@kernel.org> In-Reply-To: <20190220114217.02281bd6@gandalf.local.home> References: <20190215174712.372898450@goodmis.org> <20190215174945.557218316@goodmis.org> <20190215171539.4682f0b4@gandalf.local.home> <300C4516-A093-43AE-8707-1C42486807A4@amacapital.net> <20190215191949.04604191@gandalf.local.home> <20190219111802.1d6dbaa3@gandalf.local.home> <20190219140330.5dd9e876@gandalf.local.home> <20190220171019.5e81a4946b56982f324f7c45@kernel.org> <20190220094926.0ab575b3@gandalf.local.home> <20190221010453.19538ae7ef2667371dcec34f@kernel.org> <20190220114217.02281bd6@gandalf.local.home> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 20 Feb 2019 11:42:17 -0500 Steven Rostedt wrote: > On Thu, 21 Feb 2019 01:04:53 +0900 > Masami Hiramatsu wrote: > > > > What about just adding 'u' to the end of the offset? Say you have a > > > data structure in kernel space that has a field in user space you want > > > to reference? > > > > > > > > > field_val=+8u(+0(%si)) > > > > Ah, that looks good :~) thank you for this idea! > > > > Hmm, I wonder if we should make it +u8 or u+8? as +8u may be confused > as unsigned? Like 8ULL. I don't know. Kernel developers suck at > naming :-p I like +u8 since it is easier to implement :-p. Thank you, > > > > -- Steve -- Masami Hiramatsu