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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 4D4A1C49ED7 for ; Fri, 20 Sep 2019 14:33:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2D842206C2 for ; Fri, 20 Sep 2019 14:33:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391329AbfITOd0 (ORCPT ); Fri, 20 Sep 2019 10:33:26 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36374 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388249AbfITOZI (ORCPT ); Fri, 20 Sep 2019 10:25:08 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iBJqM-0004xe-Ed; Fri, 20 Sep 2019 15:25:06 +0100 Received: from ben by deadeye with local (Exim 4.92.1) (envelope-from ) id 1iBJqH-0007yg-Bc; Fri, 20 Sep 2019 15:25:01 +0100 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, Denis Kirjanov , "Alan Stern" , "Johan Hovold" , "Greg Kroah-Hartman" Date: Fri, 20 Sep 2019 15:23:35 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 118/132] media: usb: siano: Fix general protection fault in smsusb In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 3.16.74-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern commit 31e0456de5be379b10fea0fa94a681057114a96e upstream. The syzkaller USB fuzzer found a general-protection-fault bug in the smsusb part of the Siano DVB driver. The fault occurs during probe because the driver assumes without checking that the device has both IN and OUT endpoints and the IN endpoint is ep1. By slightly rearranging the driver's initialization code, we can make the appropriate checks early on and thus avoid the problem. If the expected endpoints aren't present, the new code safely returns -ENODEV from the probe routine. Signed-off-by: Alan Stern Reported-and-tested-by: syzbot+53f029db71c19a47325a@syzkaller.appspotmail.com Reviewed-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- drivers/media/usb/siano/smsusb.c | 33 +++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) --- a/drivers/media/usb/siano/smsusb.c +++ b/drivers/media/usb/siano/smsusb.c @@ -359,6 +359,7 @@ static int smsusb_init_device(struct usb struct smsdevice_params_t params; struct smsusb_device_t *dev; int i, rc; + int in_maxp; /* create device object */ dev = kzalloc(sizeof(struct smsusb_device_t), GFP_KERNEL); @@ -372,6 +373,24 @@ static int smsusb_init_device(struct usb dev->udev = interface_to_usbdev(intf); dev->state = SMSUSB_DISCONNECTED; + for (i = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) { + struct usb_endpoint_descriptor *desc = + &intf->cur_altsetting->endpoint[i].desc; + + if (desc->bEndpointAddress & USB_DIR_IN) { + dev->in_ep = desc->bEndpointAddress; + in_maxp = usb_endpoint_maxp(desc); + } else { + dev->out_ep = desc->bEndpointAddress; + } + } + + pr_debug("in_ep = %02x, out_ep = %02x\n", dev->in_ep, dev->out_ep); + if (!dev->in_ep || !dev->out_ep) { /* Missing endpoints? */ + smsusb_term_device(intf); + return -ENODEV; + } + params.device_type = sms_get_board(board_id)->type; switch (params.device_type) { @@ -386,24 +405,12 @@ static int smsusb_init_device(struct usb /* fall-thru */ default: dev->buffer_size = USB2_BUFFER_SIZE; - dev->response_alignment = - le16_to_cpu(dev->udev->ep_in[1]->desc.wMaxPacketSize) - - sizeof(struct sms_msg_hdr); + dev->response_alignment = in_maxp - sizeof(struct sms_msg_hdr); params.flags |= SMS_DEVICE_FAMILY2; break; } - for (i = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) { - if (intf->cur_altsetting->endpoint[i].desc. bEndpointAddress & USB_DIR_IN) - dev->in_ep = intf->cur_altsetting->endpoint[i].desc.bEndpointAddress; - else - dev->out_ep = intf->cur_altsetting->endpoint[i].desc.bEndpointAddress; - } - - sms_info("in_ep = %02x, out_ep = %02x", - dev->in_ep, dev->out_ep); - params.device = &dev->udev->dev; params.buffer_size = dev->buffer_size; params.num_buffers = MAX_BUFFERS;