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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 AC021C3A5A6 for ; Thu, 19 Sep 2019 08:38:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 87B68217D6 for ; Thu, 19 Sep 2019 08:38:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388501AbfISIi0 (ORCPT ); Thu, 19 Sep 2019 04:38:26 -0400 Received: from mx2.suse.de ([195.135.220.15]:56232 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2388008AbfISIi0 (ORCPT ); Thu, 19 Sep 2019 04:38:26 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id CD99CACC2; Thu, 19 Sep 2019 08:38:24 +0000 (UTC) From: Oliver Neukum To: davem@davemloft.net, netdev@vger.kernel.org Cc: Oliver Neukum Subject: [PATCH] usbnet: sanity checking of packet sizes and device mtu Date: Thu, 19 Sep 2019 10:23:08 +0200 Message-Id: <20190919082309.23365-1-oneukum@suse.com> X-Mailer: git-send-email 2.16.4 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org After a reset packet sizes and device mtu can change and need to be reevaluated to calculate queue sizes. Malicious devices can set this to zero and we divide by it. Introduce sanity checking. Reported-and-tested-by: syzbot+6102c120be558c885f04@syzkaller.appspotmail.com Signed-off-by: Oliver Neukum --- drivers/net/usb/usbnet.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 58952a79b05f..e44849499b89 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -339,6 +339,8 @@ void usbnet_update_max_qlen(struct usbnet *dev) { enum usb_device_speed speed = dev->udev->speed; + if (!dev->rx_urb_size || !dev->hard_mtu) + goto insanity; switch (speed) { case USB_SPEED_HIGH: dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size; @@ -355,6 +357,7 @@ void usbnet_update_max_qlen(struct usbnet *dev) dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu; break; default: +insanity: dev->rx_qlen = dev->tx_qlen = 4; } } -- 2.16.4