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 22093C433FE for ; Mon, 31 Jan 2022 11:45:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378885AbiAaLnQ (ORCPT ); Mon, 31 Jan 2022 06:43:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378982AbiAaL3k (ORCPT ); Mon, 31 Jan 2022 06:29:40 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 038F7C0613F0; Mon, 31 Jan 2022 03:18:36 -0800 (PST) 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 96830611DB; Mon, 31 Jan 2022 11:18:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D71BC340E8; Mon, 31 Jan 2022 11:18:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643627915; bh=5tY0CAlJUzcoaiWnUY4WMVkJA9mAYKR3uGYW2xPE+5s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VHMlfKUKqKCdgKMHIK/lFyhD0mJuvhWcghTzz+Jf4mp2r56RmMSvuHy+BaQpQ7rZv 3M0G91Rm0WRY4y3/Z2VWXjiBbq65LJ5AV16oEr8Grtne8QdstRS1yTV3iPZSmAKFwY Bals0+HLH40MtVsIcUm1PirTp0O75v6r4ZnUo+qo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Robert Hancock Subject: [PATCH 5.16 066/200] serial: 8250: of: Fix mapped region size when using reg-offset property Date: Mon, 31 Jan 2022 11:55:29 +0100 Message-Id: <20220131105235.800044609@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220131105233.561926043@linuxfoundation.org> References: <20220131105233.561926043@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 @@ -83,8 +83,17 @@ 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) {