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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5C4BEC433F5 for ; Mon, 15 Nov 2021 17:32:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4950663231 for ; Mon, 15 Nov 2021 17:32:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236841AbhKORfH (ORCPT ); Mon, 15 Nov 2021 12:35:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:43424 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237008AbhKORQA (ORCPT ); Mon, 15 Nov 2021 12:16:00 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 91CCD63236; Mon, 15 Nov 2021 17:12:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1636996336; bh=3GcBuAxfBAEuz+0i0xtrfhjyFYeLcVFcmutChpvWn+Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RO1mdgnJALkKp/3gpURCJEL56cAAunmu4rRDvzHrrIYQOuzF0A1762d00F1SR9Qhp 3jc81Mf5sSUayoSQBg2RxuTAhjzGYyxzVG6EcInP/EF3HKAVY1HGZAc8WeSQUZxpFr DPiRFyICbqc4Q3bqA57iJsrx8eHmAHAqbkq6nTyc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Amitkumar Karwar , Johan Hovold , Brian Norris , Kalle Valo Subject: [PATCH 5.4 069/355] mwifiex: fix division by zero in fw download path Date: Mon, 15 Nov 2021 17:59:53 +0100 Message-Id: <20211115165316.038423525@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165313.549179499@linuxfoundation.org> References: <20211115165313.549179499@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: linux-kernel@vger.kernel.org From: Johan Hovold commit 89f8765a11d8df49296d92c404067f9b5c58ee26 upstream. Add the missing endpoint sanity checks to probe() to avoid division by zero in mwifiex_write_data_sync() in case a malicious device has broken descriptors (or when doing descriptor fuzz testing). Only add checks for the firmware-download boot stage, which require both command endpoints, for now. The driver looks like it will handle a missing endpoint during normal operation without oopsing, albeit not very gracefully as it will try to submit URBs to the default pipe and fail. Note that USB core will reject URBs submitted for endpoints with zero wMaxPacketSize but that drivers doing packet-size calculations still need to handle this (cf. commit 2548288b4fb0 ("USB: Fix: Don't skip endpoint descriptors with maxpacket=0")). Fixes: 4daffe354366 ("mwifiex: add support for Marvell USB8797 chipset") Cc: stable@vger.kernel.org # 3.5 Cc: Amitkumar Karwar Signed-off-by: Johan Hovold Reviewed-by: Brian Norris Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20211027080819.6675-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/marvell/mwifiex/usb.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) --- a/drivers/net/wireless/marvell/mwifiex/usb.c +++ b/drivers/net/wireless/marvell/mwifiex/usb.c @@ -505,6 +505,22 @@ static int mwifiex_usb_probe(struct usb_ } } + switch (card->usb_boot_state) { + case USB8XXX_FW_DNLD: + /* Reject broken descriptors. */ + if (!card->rx_cmd_ep || !card->tx_cmd_ep) + return -ENODEV; + if (card->bulk_out_maxpktsize == 0) + return -ENODEV; + break; + case USB8XXX_FW_READY: + /* Assume the driver can handle missing endpoints for now. */ + break; + default: + WARN_ON(1); + return -ENODEV; + } + usb_set_intfdata(intf, card); ret = mwifiex_add_card(card, &card->fw_done, &usb_ops,