From patchwork Thu Oct 27 19:24:38 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prasad Pandit X-Patchwork-Id: 9400253 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 2672D60588 for ; Thu, 27 Oct 2016 19:25:13 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 03DDB2A391 for ; Thu, 27 Oct 2016 19:25:13 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ECBF02A393; Thu, 27 Oct 2016 19:25:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C60D92A391 for ; Thu, 27 Oct 2016 19:25:11 +0000 (UTC) Received: from localhost ([::1]:44116 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bzqIY-0003y9-MV for patchwork-qemu-devel@patchwork.kernel.org; Thu, 27 Oct 2016 15:25:10 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58928) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bzqIH-0003wW-Bl for qemu-devel@nongnu.org; Thu, 27 Oct 2016 15:24:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bzqIG-0002MY-8c for qemu-devel@nongnu.org; Thu, 27 Oct 2016 15:24:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58820) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1bzqIA-0002Ff-MB; Thu, 27 Oct 2016 15:24:46 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C742333C158; Thu, 27 Oct 2016 19:24:45 +0000 (UTC) Received: from javelin.localdomain (vpn-58-122.rdu2.redhat.com [10.10.58.122]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u9RJOdq4029585 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Thu, 27 Oct 2016 15:24:42 -0400 From: P J P To: Qemu Developers Date: Fri, 28 Oct 2016 00:54:38 +0530 Message-Id: <1477596278-1470-1-git-send-email-ppandit@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Thu, 27 Oct 2016 19:24:45 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v4] char: cadence: check baud rate generator and divider values X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Prasad J Pandit , Alistair Francis , qemu-arm , "Edgar E . Iglesias" , Huawei PSIRT Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Prasad J Pandit The Cadence UART device emulator calculates speed by dividing the baud rate by a 'baud rate generator' & 'baud rate divider' value. The device specification defines these register values to be non-zero and within certain limits. Add checks for these limits to avoid errors like divide by zero. Reported-by: Huawei PSIRT Signed-off-by: Prasad J Pandit Reviewed-by: Alistair Francis --- hw/char/cadence_uart.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) Update: remove default reset value assignment. -> https://lists.gnu.org/archive/html/qemu-devel/2016-10/msg07206.html diff --git a/hw/char/cadence_uart.c b/hw/char/cadence_uart.c index e3bc52f..4a3c4c6 100644 --- a/hw/char/cadence_uart.c +++ b/hw/char/cadence_uart.c @@ -1,6 +1,11 @@ /* * Device model for Cadence UART * + * Reference: Xilinx Zynq 7000 reference manual + * - http://www.xilinx.com/support/documentation/user_guides/ug585-Zynq-7000-TRM.pdf + * - Chapter 19 UART Controller + * - Appendix B for Register details + * * Copyright (c) 2010 Xilinx Inc. * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com) * Copyright (c) 2012 PetaLogix Pty Ltd. @@ -410,6 +415,16 @@ static void uart_write(void *opaque, hwaddr offset, break; } break; + case R_BRGR: /* Baud rate generator */ + if (value >= 0x01) { + s->r[offset] = value & 0xFFFF; + } + break; + case R_BDIV: /* Baud rate divider */ + if (value >= 0x04) { + s->r[offset] = value & 0xFF; + } + break; default: s->r[offset] = value; }