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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BFEF6C433F5 for ; Mon, 31 Jan 2022 10:58:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244556AbiAaK6f (ORCPT ); Mon, 31 Jan 2022 05:58:35 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:59668 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240779AbiAaK6Z (ORCPT ); Mon, 31 Jan 2022 05:58:25 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E72F860AD6; Mon, 31 Jan 2022 10:58:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD864C340E8; Mon, 31 Jan 2022 10:58:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643626704; bh=EClu4GjrOR5bHAUlw9/tGEzgEjXffrX+eOks0piuWQA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q701v+6UQu+bf4Hd38zvFvr2Y4hkFa59z9GEahniQW7ZuCuZP7Eq4hq5DjLl3fWwI RgoK+QpJK4P4ehsDLCM/SttONpKExXpi6EzW78Omv1Hy/D6k0aEZNx8JwS7HePH4Nv pPoiSI47TNhjI+cluJvHjigRkOSgUtwmb7z9wWhs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Robert Hancock Subject: [PATCH 5.4 13/64] serial: 8250: of: Fix mapped region size when using reg-offset property Date: Mon, 31 Jan 2022 11:55:58 +0100 Message-Id: <20220131105216.106208598@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220131105215.644174521@linuxfoundation.org> References: <20220131105215.644174521@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Robert Hancock commit d06b1cf28297e27127d3da54753a3a01a2fa2f28 upstream. 8250_of supports a reg-offset property which is intended to handle cases where the device registers start at an offset inside the region of memory allocated to the device. The Xilinx 16550 UART, for which this support was initially added, requires this. However, the code did not adjust the overall size of the mapped region accordingly, causing the driver to request an area of memory past the end of the device's allocation. For example, if the UART was allocated an address of 0xb0130000, size of 0x10000 and reg-offset of 0x1000 in the device tree, the region of memory reserved was b0131000-b0140fff, which caused the driver for the region starting at b0140000 to fail to probe. Fix this by subtracting reg-offset from the mapped region size. Fixes: b912b5e2cfb3 ([POWERPC] Xilinx: of_serial support for Xilinx uart 16550.) Cc: stable Signed-off-by: Robert Hancock Link: https://lore.kernel.org/r/20220112194214.881844-1-robert.hancock@calian.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_of.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) --- a/drivers/tty/serial/8250/8250_of.c +++ b/drivers/tty/serial/8250/8250_of.c @@ -105,8 +105,17 @@ static int of_platform_serial_setup(stru port->mapsize = resource_size(&resource); /* Check for shifted address mapping */ - if (of_property_read_u32(np, "reg-offset", &prop) == 0) + if (of_property_read_u32(np, "reg-offset", &prop) == 0) { + if (prop >= port->mapsize) { + dev_warn(&ofdev->dev, "reg-offset %u exceeds region size %pa\n", + prop, &port->mapsize); + ret = -EINVAL; + goto err_unprepare; + } + port->mapbase += prop; + port->mapsize -= prop; + } port->iotype = UPIO_MEM; if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {