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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 324F3C43603 for ; Wed, 18 Dec 2019 10:35:49 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E2294218AC for ; Wed, 18 Dec 2019 10:35:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="bmk9P5dA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E2294218AC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: MIME-Version:Message-ID:In-Reply-To:Date:References:Subject:To:From:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7PRzv7udjNM2jx0BWQraPA1YkX5ozHqkifg+caGb7KM=; b=bmk9P5dAgEBFFKQO825pUnXCT dveAbm3GFQk+F5TXH1kXb0s5hD14XikGUWnhizegL4K5zCSpX+s4QHmGNCrHhDeRs8z0Rd4xA9SJp B4X6UmF8tqIbBt1QM0qQZ8pPEzrerms4Jd6j112E8f5XxuENwxTOr2FRwJZVv0F2BmTlixfGpiebq QqQUif5GkYll8u2kd6w2mNRF+6hNE/S8U/26uc/E3RmE1DXeTyvuaZPwPb4HUXgv7xoYyTkwrHLC5 C5aZ5CSKT9vfzuBRLslKErqGIi0uEXdqjula+ltZXWVPeY5IysWIwl2ZrU43q/rTG2G2GEU55dm8h A5GnuocVA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ihWgE-0002ZH-7U; Wed, 18 Dec 2019 10:35:46 +0000 Received: from mx2.suse.de ([195.135.220.15]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1ihWfx-0002Gp-Hf for linux-riscv@lists.infradead.org; Wed, 18 Dec 2019 10:35:33 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 5FF2BAD05; Wed, 18 Dec 2019 10:35:27 +0000 (UTC) From: Andreas Schwab To: David Abdurachmanov Subject: Re: [PATCH] riscv: reject invalid syscalls below -1 References: <20191218084757.904971-1-david.abdurachmanov@sifive.com> X-Yow: I was in EXCRUCIATING PAIN until I started reading JACK AND JILL Magazine!! Date: Wed, 18 Dec 2019 11:35:26 +0100 In-Reply-To: (David Abdurachmanov's message of "Wed, 18 Dec 2019 12:06:57 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191218_023529_846462_97E76A04 X-CRM114-Status: GOOD ( 12.07 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Albert Ou , Kees Cook , David Abdurachmanov , Anup Patel , "linux-kernel@vger.kernel.org List" , linux-riscv , Vincent Chen , Palmer Dabbelt , Paul Walmsley , Thomas Gleixner , Bin Meng , Valentin Schneider Sender: "linux-riscv" Errors-To: linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org On Dez 18 2019, David Abdurachmanov wrote: > On Wed, Dec 18, 2019 at 11:46 AM Andreas Schwab wrote: >> >> On Dez 18 2019, David Abdurachmanov wrote: >> >> > diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S >> > index a1349ca64669..e163b7b64c86 100644 >> > --- a/arch/riscv/kernel/entry.S >> > +++ b/arch/riscv/kernel/entry.S >> > @@ -246,6 +246,7 @@ check_syscall_nr: >> > */ >> > li t1, -1 >> > beq a7, t1, ret_from_syscall_rejected >> > + blt a7, t1, 1f >> >> How about using bgeu instead in the preceding check? > > The syscall number could be -1 if tracer rejected it. So check for -1 first, then for out-of-range? Andreas. -- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different." 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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,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 E4557C43603 for ; Wed, 18 Dec 2019 10:35:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BFEED227BF for ; Wed, 18 Dec 2019 10:35:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726856AbfLRKf3 (ORCPT ); Wed, 18 Dec 2019 05:35:29 -0500 Received: from mx2.suse.de ([195.135.220.15]:36810 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725785AbfLRKf3 (ORCPT ); Wed, 18 Dec 2019 05:35:29 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 5FF2BAD05; Wed, 18 Dec 2019 10:35:27 +0000 (UTC) From: Andreas Schwab To: David Abdurachmanov Cc: Paul Walmsley , Palmer Dabbelt , Albert Ou , David Abdurachmanov , Kees Cook , Anup Patel , Vincent Chen , Valentin Schneider , Thomas Gleixner , Bin Meng , linux-riscv , "linux-kernel\@vger.kernel.org List" Subject: Re: [PATCH] riscv: reject invalid syscalls below -1 References: <20191218084757.904971-1-david.abdurachmanov@sifive.com> X-Yow: I was in EXCRUCIATING PAIN until I started reading JACK AND JILL Magazine!! Date: Wed, 18 Dec 2019 11:35:26 +0100 In-Reply-To: (David Abdurachmanov's message of "Wed, 18 Dec 2019 12:06:57 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Dez 18 2019, David Abdurachmanov wrote: > On Wed, Dec 18, 2019 at 11:46 AM Andreas Schwab wrote: >> >> On Dez 18 2019, David Abdurachmanov wrote: >> >> > diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S >> > index a1349ca64669..e163b7b64c86 100644 >> > --- a/arch/riscv/kernel/entry.S >> > +++ b/arch/riscv/kernel/entry.S >> > @@ -246,6 +246,7 @@ check_syscall_nr: >> > */ >> > li t1, -1 >> > beq a7, t1, ret_from_syscall_rejected >> > + blt a7, t1, 1f >> >> How about using bgeu instead in the preceding check? > > The syscall number could be -1 if tracer rejected it. So check for -1 first, then for out-of-range? Andreas. -- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different."