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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 496D1C6FA99 for ; Fri, 10 Mar 2023 20:05:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D01AF6B0071; Fri, 10 Mar 2023 15:05:37 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C8AA88E0002; Fri, 10 Mar 2023 15:05:37 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B039F8E0001; Fri, 10 Mar 2023 15:05:37 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id A0B5E6B0071 for ; Fri, 10 Mar 2023 15:05:37 -0500 (EST) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 64B5AC069F for ; Fri, 10 Mar 2023 20:05:37 +0000 (UTC) X-FDA: 80554068714.15.FEF1BEE Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by imf26.hostedemail.com (Postfix) with ESMTP id 1AA2E140007 for ; Fri, 10 Mar 2023 20:05:29 +0000 (UTC) Authentication-Results: imf26.hostedemail.com; dkim=temperror ("DNS error when getting key") header.d=alien8.de header.s=dkim header.b=OB18JSyE; dmarc=temperror reason="SPF/DKIM temp error" header.from=alien8.de (policy=temperror); spf=temperror (imf26.hostedemail.com: error in processing during lookup of bp@alien8.de: DNS error) smtp.mailfrom=bp@alien8.de ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1678478735; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=LxdcVjTex/5D1F21dsooykzTuaD2TSooCSq9ywUUbCo=; b=ihY0txKxO3dxFbwtrHiwawkd8GKnOSyeJ4+r0PgsaVtnN4FglyDzUCFqguFtr75tg430sJ tAcuWWVFMKsRf1ao65VRCnLEF1rYoVQMsFqmOYotcXdsQPERltSaO2bd03mwuoABFwi7Ou OeRcU37EobmaNGNjfZe1VD8pEhU9obk= ARC-Authentication-Results: i=1; imf26.hostedemail.com; dkim=temperror ("DNS error when getting key") header.d=alien8.de header.s=dkim header.b=OB18JSyE; dmarc=temperror reason="SPF/DKIM temp error" header.from=alien8.de (policy=temperror); spf=temperror (imf26.hostedemail.com: error in processing during lookup of bp@alien8.de: DNS error) smtp.mailfrom=bp@alien8.de ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1678478735; a=rsa-sha256; cv=none; b=3tetmVcJ/y1Bk9TkjraGJDzcHb1+EJcHE6e+lryfSrwUHzkffRDF38nE05+9M2J5vCgfvd EpJkJ369VLdHM6HRLlP3qpR77f/SCsIzWYjCntdsm2eM2BF51h+Rd2kxaLScAI2mYKAYaC nUIpeGWNiMD0WlD50tDrJAtPLj+HQEM= Received: from zn.tnic (p5de8e9fe.dip0.t-ipconnect.de [93.232.233.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 9FA451EC0505; Fri, 10 Mar 2023 21:05:24 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1678478724; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=LxdcVjTex/5D1F21dsooykzTuaD2TSooCSq9ywUUbCo=; b=OB18JSyEdXi4pf5angNvJJKWTx+eE2riAiW7HZ8+/koQuO8c7cn9BCKwos+7vWXzK3bqe9 gI5QFueasqn8lGgpHOzIQpqvyWwSNr6wPX30zwl9MVbWoY3VHuxGT6B2sLbgl5ZUxzrzU5 2XmSXnM+O6phpIyuU4WoRuNqm5zDS7Y= Date: Fri, 10 Mar 2023 21:05:19 +0100 From: Borislav Petkov To: "Edgecombe, Rick P" Cc: "david@redhat.com" , "bsingharora@gmail.com" , "hpa@zytor.com" , "Syromiatnikov, Eugene" , "peterz@infradead.org" , "rdunlap@infradead.org" , "keescook@chromium.org" , "dave.hansen@linux.intel.com" , "kirill.shutemov@linux.intel.com" , "Eranian, Stephane" , "linux-mm@kvack.org" , "fweimer@redhat.com" , "nadav.amit@gmail.com" , "jannh@google.com" , "dethoma@microsoft.com" , "kcc@google.com" , "linux-arch@vger.kernel.org" , "pavel@ucw.cz" , "oleg@redhat.com" , "hjl.tools@gmail.com" , "Yang, Weijiang" , "Lutomirski, Andy" , "linux-doc@vger.kernel.org" , "arnd@arndb.de" , "tglx@linutronix.de" , "Schimpe, Christina" , "mike.kravetz@oracle.com" , "x86@kernel.org" , "akpm@linux-foundation.org" , "debug@rivosinc.com" , "jamorris@linux.microsoft.com" , "john.allen@amd.com" , "rppt@kernel.org" , "andrew.cooper3@citrix.com" , "mingo@redhat.com" , "corbet@lwn.net" , "linux-kernel@vger.kernel.org" , "linux-api@vger.kernel.org" , "gorcunov@gmail.com" Subject: Re: [PATCH v7 33/41] x86/shstk: Introduce map_shadow_stack syscall Message-ID: <20230310200519.GDZAuNf+bvYjGtazqv@fat_crate.local> References: <20230227222957.24501-1-rick.p.edgecombe@intel.com> <20230227222957.24501-34-rick.p.edgecombe@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 1AA2E140007 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: 6dxbpx7yt5ipuzfjkmwwz997n7j4zg9d X-HE-Tag: 1678478729-368463 X-HE-Meta: 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 Qqhd2aJr 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Mar 10, 2023 at 05:12:40PM +0000, Edgecombe, Rick P wrote: > > Can we use distinct negative retvals in each case so that it is clear > > to > > userspace where it fails, *if* it fails? > > Good idea, I think maybe ERANGE. For those two, right? /* If there isn't space for a token */ if (set_tok && size < 8) return -EINVAL; if (addr && addr <= 0xFFFFFFFF) return -EINVAL; They are kinda range-checking of sorts. A wider range but still similar... -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette