From patchwork Mon Nov 6 14:32:18 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Bj=C3=B8rn_Mork?= X-Patchwork-Id: 834770 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=mork.no header.i=@mork.no header.b="Y+3S+jYW"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3yVw5H4y08z9ryT for ; Tue, 7 Nov 2017 01:32:51 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932165AbdKFOct (ORCPT ); Mon, 6 Nov 2017 09:32:49 -0500 Received: from canardo.mork.no ([148.122.252.1]:59229 "EHLO canardo.mork.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752489AbdKFOcs (ORCPT ); Mon, 6 Nov 2017 09:32:48 -0500 Received: from miraculix.mork.no ([IPv6:2a02:2121:305:5f9:34c0:14ff:fe74:3b2f]) (authenticated bits=0) by canardo.mork.no (8.15.2/8.15.2) with ESMTPSA id vA6EWdlt029379 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 6 Nov 2017 15:32:39 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mork.no; s=b; t=1509978760; bh=K01ntvmrRKrFJAiSymqzL2UYB/ZWn/8C3vGlvscDX84=; h=From:To:Cc:Subject:Date:Message-Id:From; b=Y+3S+jYWhR8Dw8F+CU+xICGFq7Dgw+nppty+A31qUy1scDhukAXOMhOUqhCyzkcb2 nk5pyeYuS4ParLHWzs9yzK5C5WzyrfTXZUVGBgxChx+sEqx+I5NXFvonqKJq0I2y/u WByuCg3kjWvPoSR8Y6c8yXayQmJ1HOY4cjQPCuio= Received: from bjorn by miraculix.mork.no with local (Exim 4.89) (envelope-from ) id 1eBiS2-0000l8-AR; Mon, 06 Nov 2017 15:32:34 +0100 From: =?utf-8?q?Bj=C3=B8rn_Mork?= To: netdev@vger.kernel.org Cc: linux-usb@vger.kernel.org, Oliver Neukum , Dmitry Vyukov , Kostya Serebryany , syzkaller@googlegroups.com, =?utf-8?q?Bj=C3=B8rn_Mork?= Subject: [PATCH net, stable] net: qmi_wwan: fix divide by 0 on bad descriptors Date: Mon, 6 Nov 2017 15:32:18 +0100 Message-Id: <20171106143218.2880-1-bjorn@mork.no> X-Mailer: git-send-email 2.11.0 MIME-Version: 1.0 X-Virus-Scanned: clamav-milter 0.99.2 at canardo X-Virus-Status: Clean Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org A CDC Ethernet functional descriptor with wMaxSegmentSize = 0 will cause a divide error in usbnet_probe: divide error: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc8-44453-g1fdc1a82c34f #56 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Workqueue: usb_hub_wq hub_event task: ffff88006bef5c00 task.stack: ffff88006bf60000 RIP: 0010:usbnet_update_max_qlen+0x24d/0x390 drivers/net/usb/usbnet.c:355 RSP: 0018:ffff88006bf67508 EFLAGS: 00010246 RAX: 00000000000163c8 RBX: ffff8800621fce40 RCX: ffff8800621fcf34 RDX: 0000000000000000 RSI: ffffffff837ecb7a RDI: ffff8800621fcf34 RBP: ffff88006bf67520 R08: ffff88006bef5c00 R09: ffffed000c43f881 R10: ffffed000c43f880 R11: ffff8800621fc406 R12: 0000000000000003 R13: ffffffff85c71de0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88006ca00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe9c0d6dac CR3: 00000000614f4000 CR4: 00000000000006f0 Call Trace: usbnet_probe+0x18b5/0x2790 drivers/net/usb/usbnet.c:1783 qmi_wwan_probe+0x133/0x220 drivers/net/usb/qmi_wwan.c:1338 usb_probe_interface+0x324/0x940 drivers/usb/core/driver.c:361 really_probe drivers/base/dd.c:413 driver_probe_device+0x522/0x740 drivers/base/dd.c:557 Fix by simply ignoring the bogus descriptor, as it is optional for QMI devices anyway. Fixes: 423ce8caab7e ("net: usb: qmi_wwan: New driver for Huawei QMI based WWAN devices") Reported-by: Andrey Konovalov Signed-off-by: Bjørn Mork --- drivers/net/usb/qmi_wwan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index 8c3733608271..a4f229edcceb 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -681,7 +681,7 @@ static int qmi_wwan_bind(struct usbnet *dev, struct usb_interface *intf) } /* errors aren't fatal - we can live with the dynamic address */ - if (cdc_ether) { + if (cdc_ether && cdc_ether->wMaxSegmentSize) { dev->hard_mtu = le16_to_cpu(cdc_ether->wMaxSegmentSize); usbnet_get_ethernet_addr(dev, cdc_ether->iMACAddress); }