From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v2] usbnet: remove generic hard_header_len check Date: Mon, 17 Feb 2014 14:36:06 -0500 (EST) Message-ID: <20140217.143606.1431722446347147819.davem@davemloft.net> References: <1392310219-5719-1-git-send-email-emilgoode@gmail.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: steve.glendinning@shawell.net, oneukum@suse.de, bjorn@mork.no, freddy@asix.com.tw, edumazet@google.com, ming.lei@canonical.com, paul.gortmaker@windriver.com, jeffrey.t.kirsher@intel.com, liujunliang_ljl@163.com, octavian.purdila@intel.com, linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: emilgoode@gmail.com Return-path: In-Reply-To: <1392310219-5719-1-git-send-email-emilgoode@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Emil Goode Date: Thu, 13 Feb 2014 17:50:19 +0100 > This patch removes a generic hard_header_len check from the usbnet > module that is causing dropped packages under certain circumstances > for devices that send rx packets that cross urb boundaries. > > One example is the AX88772B which occasionally send rx packets that > cross urb boundaries where the remaining partial packet is sent with > no hardware header. When the buffer with a partial packet is of less > number of octets than the value of hard_header_len the buffer is > discarded by the usbnet module. > > With AX88772B this can be reproduced by using ping with a packet > size between 1965-1976. > > The bug has been reported here: > > https://bugzilla.kernel.org/show_bug.cgi?id=29082 > > This patch introduces the following changes: > - Removes the generic hard_header_len check in the rx_complete > function in the usbnet module. > - Introduces a ETH_HLEN check for skbs that are not cloned from > within a rx_fixup callback. > - For safety a hard_header_len check is added to each rx_fixup > callback function that could be affected by this change. > These extra checks could possibly be removed by someone > who has the hardware to test. > - Removes a call to dev_kfree_skb_any() and instead utilizes the > dev->done list to queue skbs for cleanup. > > The changes place full responsibility on the rx_fixup callback > functions that clone skbs to only pass valid skbs to the > usbnet_skb_return function. > > Signed-off-by: Emil Goode > Reported-by: Igor Gnatenko Applied and queued up for -stable, thanks.