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 26102C43603 for ; Wed, 18 Dec 2019 09:46:13 +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 F1A8424650 for ; Wed, 18 Dec 2019 09:46:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="I7qEDWm7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1A8424650 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=e8WeEOX86xa99BoNrQ9B2Du4gOsUH/gMEvyPBCHtlrA=; b=I7qEDWm78XjPu9WUNtQdssNWU UTJVfKe4tGIKNWAfFRiVl6AgARMEsP1ES+8yTNqX2XS1Iu1Hu3BY+0wzRob6yR6AP4R9FgCZoXWQs tRUexQBFuU/liFmw8TlkeR7SjOtVyUGJUYcOEpIwmoWbLS1WOlpyaQdZRJbQvJTEquPCh9zQTBgxQ uUeWIK9aNVA0XkcOMzi+QtnwaHlt5SG2YAWuqlgMt8K/gDHPeEKZv5P4xD1NyZ9dAct7r8rehLD75 v0GpMv+EnNMvjMOoHRqnyEFZ7Hm/nj52tSp4dTajQFnbriml7jfs5Wbk4EuAApj8xRo/F8M03fA+l txJ2fph4w==; 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 1ihVuF-0000Zp-Ok; Wed, 18 Dec 2019 09:46:11 +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 1ihVuD-0000ZS-EJ for linux-riscv@lists.infradead.org; Wed, 18 Dec 2019 09:46:10 +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 78232ADCB; Wed, 18 Dec 2019 09:46:07 +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: Here I am in the POSTERIOR OLFACTORY LOBULE but I don't see CARL SAGAN anywhere!! Date: Wed, 18 Dec 2019 10:46:06 +0100 In-Reply-To: <20191218084757.904971-1-david.abdurachmanov@sifive.com> (David Abdurachmanov's message of "Wed, 18 Dec 2019 10:47:56 +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_014609_627842_725075A3 X-CRM114-Status: GOOD ( 10.96 ) 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, linux-riscv@lists.infradead.org, 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: > 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? /* * Syscall number held in a7. * If syscall number is above allowed value, redirect to ni_syscall. */ bge a7, t0, 1f 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."