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 5BA13C433EF for ; Mon, 24 Jan 2022 20:41:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1388837AbiAXUkM (ORCPT ); Mon, 24 Jan 2022 15:40:12 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:60552 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1386929AbiAXUgI (ORCPT ); Mon, 24 Jan 2022 15:36:08 -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 7DD4061540; Mon, 24 Jan 2022 20:36:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85476C340EB; Mon, 24 Jan 2022 20:36:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643056567; bh=aXgAlWjFhuTYaGo0IQrs5NxFaBkHUtQAgDjh1OBwC9o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eRDFt8ZChE/aVx24xQhSvrsG2lgkzOHdVgZYtgU6h+cRHaNrIzJSCbNh6La03XRod 9NJbZ0Zhkp+91aaEoQm77XXN7cnuwtP+UgV9pLd85Y4fIaUQZdBnFq+u7Q+yNFGSaa kbusGGn81JLO5c5zS2kHKb047W/sDe2omT21okNU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, rkardell@mida.se, Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 5.15 527/846] media: m920x: dont use stack on USB reads Date: Mon, 24 Jan 2022 19:40:44 +0100 Message-Id: <20220124184119.182953737@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184100.867127425@linuxfoundation.org> References: <20220124184100.867127425@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: stable@vger.kernel.org From: Mauro Carvalho Chehab [ Upstream commit a2ab06d7c4d6bfd0b545a768247a70463e977e27 ] Using stack-allocated pointers for USB message data don't work. This driver is almost OK with that, except for the I2C read logic. Fix it by using a temporary read buffer, just like on all other calls to m920x_read(). Link: https://lore.kernel.org/all/ccc99e48-de4f-045e-0fe4-61e3118e3f74@mida.se/ Reported-by: rkardell@mida.se Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/usb/dvb-usb/m920x.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/media/usb/dvb-usb/m920x.c b/drivers/media/usb/dvb-usb/m920x.c index 4bb5b82599a79..691e05833db19 100644 --- a/drivers/media/usb/dvb-usb/m920x.c +++ b/drivers/media/usb/dvb-usb/m920x.c @@ -274,6 +274,13 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu /* Should check for ack here, if we knew how. */ } if (msg[i].flags & I2C_M_RD) { + char *read = kmalloc(1, GFP_KERNEL); + if (!read) { + ret = -ENOMEM; + kfree(read); + goto unlock; + } + for (j = 0; j < msg[i].len; j++) { /* Last byte of transaction? * Send STOP, otherwise send ACK. */ @@ -281,9 +288,12 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu if ((ret = m920x_read(d->udev, M9206_I2C, 0x0, 0x20 | stop, - &msg[i].buf[j], 1)) != 0) + read, 1)) != 0) goto unlock; + msg[i].buf[j] = read[0]; } + + kfree(read); } else { for (j = 0; j < msg[i].len; j++) { /* Last byte of transaction? Then send STOP. */ -- 2.34.1