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 X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62A71C433DB for ; Fri, 26 Feb 2021 10:58:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 194CB64EE1 for ; Fri, 26 Feb 2021 10:58:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230384AbhBZK6U (ORCPT ); Fri, 26 Feb 2021 05:58:20 -0500 Received: from mail.kernel.org ([198.145.29.99]:59620 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229556AbhBZK6P (ORCPT ); Fri, 26 Feb 2021 05:58:15 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3816964EE1; Fri, 26 Feb 2021 10:57:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1614337055; bh=00rc4RUiQWZ4q7RnENrzGetH5T02eUu9IMxTo8Kdgjc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hhWtCujebkitKYQm4YIa58nOtrACAyc9BbCc1w2h0yDcL2d13EEzOFfpAIFu4dIRw FTJlZH7w2jAFCIEnHlCPMV8sdAkEilYJOHZbA3tbIcOabDiOW36q0MwSOqMeUvL1hO i+LNzo/q1Cr7iVXU+KNY/pSInllfNGhY2RXyuy6SJptZmngwN5Ry7kxYim0eKGsMAp 8t9t5akqw8O75pi/Mofs/2GKA0BunbsUssMKq3riNLxwoEKxDSqKnV6yoVxtmXHC4o BY/aikGhGgLfPYgjfXhk45kfODtG9UaE3eti+sPXoanpqfNFHJXS0KWp/rSm8K9msU wQne/sl5YNdqw== Date: Fri, 26 Feb 2021 16:27:29 +0530 From: Manivannan Sadhasivam To: Johan Hovold Cc: linux-usb@vger.kernel.org, Mauro Carvalho Chehab , linux-kernel@vger.kernel.org Subject: Re: [PATCH] USB: serial: xr: fix NULL-deref on disconnect Message-ID: <20210226105729.GA7069@work> References: <20210226100826.18987-1-johan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210226100826.18987-1-johan@kernel.org> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 26, 2021 at 11:08:26AM +0100, Johan Hovold wrote: > Claiming the sibling control interface is a bit more involved and > specifically requires adding support to USB-serial core for managing > either interface being unbound first, something which could otherwise > lead to a NULL-pointer dereference. > > Similarly, additional infrastructure is also needed to handle suspend > properly. > > Since the driver currently isn't actually using the control interface, > we can defer this for now by simply not claiming the control interface. > > Fixes: c2d405aa86b4 ("USB: serial: add MaxLinear/Exar USB to Serial driver") > Reported-by: Mauro Carvalho Chehab > Cc: Manivannan Sadhasivam > Signed-off-by: Johan Hovold Reviewed-by: Manivannan Sadhasivam Thanks, Mani > --- > drivers/usb/serial/xr_serial.c | 25 ------------------------- > 1 file changed, 25 deletions(-) > > diff --git a/drivers/usb/serial/xr_serial.c b/drivers/usb/serial/xr_serial.c > index 483d07dee19d..0ca04906da4b 100644 > --- a/drivers/usb/serial/xr_serial.c > +++ b/drivers/usb/serial/xr_serial.c > @@ -545,37 +545,13 @@ static void xr_close(struct usb_serial_port *port) > > static int xr_probe(struct usb_serial *serial, const struct usb_device_id *id) > { > - struct usb_driver *driver = serial->type->usb_driver; > - struct usb_interface *control_interface; > - int ret; > - > /* Don't bind to control interface */ > if (serial->interface->cur_altsetting->desc.bInterfaceNumber == 0) > return -ENODEV; > > - /* But claim the control interface during data interface probe */ > - control_interface = usb_ifnum_to_if(serial->dev, 0); > - if (!control_interface) > - return -ENODEV; > - > - ret = usb_driver_claim_interface(driver, control_interface, NULL); > - if (ret) { > - dev_err(&serial->interface->dev, "Failed to claim control interface\n"); > - return ret; > - } > - > return 0; > } > > -static void xr_disconnect(struct usb_serial *serial) > -{ > - struct usb_driver *driver = serial->type->usb_driver; > - struct usb_interface *control_interface; > - > - control_interface = usb_ifnum_to_if(serial->dev, 0); > - usb_driver_release_interface(driver, control_interface); > -} > - > static const struct usb_device_id id_table[] = { > { USB_DEVICE(0x04e2, 0x1410) }, /* XR21V141X */ > { } > @@ -590,7 +566,6 @@ static struct usb_serial_driver xr_device = { > .id_table = id_table, > .num_ports = 1, > .probe = xr_probe, > - .disconnect = xr_disconnect, > .open = xr_open, > .close = xr_close, > .break_ctl = xr_break_ctl, > -- > 2.26.2 >