Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752519AbdFAQh1 (ORCPT ); Thu, 1 Jun 2017 12:37:27 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33168 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751902AbdFAPok (ORCPT ); Thu, 1 Jun 2017 11:44:40 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Greg Kroah-Hartman" , "Johan Hovold" Date: Thu, 01 Jun 2017 16:43:15 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 045/212] USB: serial: io_edgeport: fix epic-descriptor handling In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2663 Lines: 77 3.16.44-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit e4457d9798adb96272468e93da663de9bd0a4198 upstream. Use a dedicated buffer for the DMA transfer and make sure to detect short transfers to avoid parsing a corrupt descriptor. Fixes: 6e8cf7751f9f ("USB: add EPIC support to the io_edgeport driver") Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold Signed-off-by: Ben Hutchings --- drivers/usb/serial/io_edgeport.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) --- a/drivers/usb/serial/io_edgeport.c +++ b/drivers/usb/serial/io_edgeport.c @@ -492,20 +492,24 @@ static int get_epic_descriptor(struct ed int result; struct usb_serial *serial = ep->serial; struct edgeport_product_info *product_info = &ep->product_info; - struct edge_compatibility_descriptor *epic = &ep->epic_descriptor; + struct edge_compatibility_descriptor *epic; struct edge_compatibility_bits *bits; struct device *dev = &serial->dev->dev; ep->is_epic = 0; + + epic = kmalloc(sizeof(*epic), GFP_KERNEL); + if (!epic) + return -ENOMEM; + result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0), USB_REQUEST_ION_GET_EPIC_DESC, 0xC0, 0x00, 0x00, - &ep->epic_descriptor, - sizeof(struct edge_compatibility_descriptor), + epic, sizeof(*epic), 300); - - if (result > 0) { + if (result == sizeof(*epic)) { ep->is_epic = 1; + memcpy(&ep->epic_descriptor, epic, sizeof(*epic)); memset(product_info, 0, sizeof(struct edgeport_product_info)); product_info->NumPorts = epic->NumPorts; @@ -534,8 +538,16 @@ static int get_epic_descriptor(struct ed dev_dbg(dev, " IOSPWriteLCR : %s\n", bits->IOSPWriteLCR ? "TRUE": "FALSE"); dev_dbg(dev, " IOSPSetBaudRate : %s\n", bits->IOSPSetBaudRate ? "TRUE": "FALSE"); dev_dbg(dev, " TrueEdgeport : %s\n", bits->TrueEdgeport ? "TRUE": "FALSE"); + + result = 0; + } else if (result >= 0) { + dev_warn(&serial->interface->dev, "short epic descriptor received: %d\n", + result); + result = -EIO; } + kfree(epic); + return result; } @@ -2789,7 +2801,7 @@ static int edge_startup(struct usb_seria dev_info(&serial->dev->dev, "%s detected\n", edge_serial->name); /* Read the epic descriptor */ - if (get_epic_descriptor(edge_serial) <= 0) { + if (get_epic_descriptor(edge_serial) < 0) { /* memcpy descriptor to Supports structures */ memcpy(&edge_serial->epic_descriptor.Supports, descriptor, sizeof(struct edge_compatibility_bits));