From patchwork Tue Oct 26 09:52:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 12584395 X-Patchwork-Delegate: kvalo@adurom.com 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 2E3AFC4332F for ; Tue, 26 Oct 2021 09:53:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0A6FE60F24 for ; Tue, 26 Oct 2021 09:53:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234725AbhJZJzk (ORCPT ); Tue, 26 Oct 2021 05:55:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:58232 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233662AbhJZJzk (ORCPT ); Tue, 26 Oct 2021 05:55:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6E54561074; Tue, 26 Oct 2021 09:53:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1635241996; bh=5Kjj92OAxcYzSBaJWYZyRkbxJVmWOj10eLL8DwNGxak=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=flGfxM41C7RvkKpC8A340v+CRDotEaOtf+/7+tlsgzZhJII5sgP++DMH2rxrJJk53 xr/aTSWjBjiqqWHTrNtBHdUxC3w+zKVlxxtI1L9VdaKQBLRyY4s53OrkI7N1GkJjVM w/hCk1fc/iRtZvpECXrEE7fev+8uCCrOSmF5h57IsCPocz8Ru+SW0YCAy48nWDXs7/ XIhn0T87kM/DTTh6NN48eRT51a+0W2+wWAMheNyvRCqaY+H8xP8q6WQnm8eA9l2Sb9 o95Uhw8mUoZtKbrV8O6oTuNfwWwJXhdw292tDQClMiRYtj66/wVxF/7TCelLUPMt7Q Jpoej/5dExAYw== Received: from johan by xi.lan with local (Exim 4.94.2) (envelope-from ) id 1mfJ8e-0006sW-4j; Tue, 26 Oct 2021 11:53:00 +0200 From: Johan Hovold To: Kalle Valo Cc: Amitkumar Karwar , Ganapathi Bhat , Sharvari Harisangam , Xinming Hu , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org, Amitkumar Karwar Subject: [PATCH 3/3] mwifiex: fix division by zero in fw download path Date: Tue, 26 Oct 2021 11:52:14 +0200 Message-Id: <20211026095214.26375-3-johan@kernel.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211026095214.26375-1-johan@kernel.org> References: <20211026095214.26375-1-johan@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Add the missing endpoint max-packet sanity check 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). 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 --- drivers/net/wireless/marvell/mwifiex/usb.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/wireless/marvell/mwifiex/usb.c b/drivers/net/wireless/marvell/mwifiex/usb.c index 426e39d4ccf0..2826654907d9 100644 --- a/drivers/net/wireless/marvell/mwifiex/usb.c +++ b/drivers/net/wireless/marvell/mwifiex/usb.c @@ -502,6 +502,9 @@ static int mwifiex_usb_probe(struct usb_interface *intf, atomic_set(&card->tx_cmd_urb_pending, 0); card->bulk_out_maxpktsize = le16_to_cpu(epd->wMaxPacketSize); + /* Reject broken descriptors. */ + if (card->bulk_out_maxpktsize == 0) + return -ENODEV; } }