Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934000Ab1ESSIb (ORCPT ); Thu, 19 May 2011 14:08:31 -0400 Received: from out2.smtp.messagingengine.com ([66.111.4.26]:39584 "EHLO out2.smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933939Ab1ESSI3 (ORCPT ); Thu, 19 May 2011 14:08:29 -0400 X-Sasl-enc: W9SDjnxO5CJbA6fXm3hAHO7wiApYCPt47GEsHtJM7O2U 1305828508 X-Mailbox-Line: From gregkh@clark.kroah.org Thu May 19 11:05:57 2011 Message-Id: <20110519180557.180377156@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Thu, 19 May 2011 11:04:58 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Ben Hutchings , "David S. Miller" Subject: [30/71] ipheth: Properly distinguish length and alignment in URBs and skbs In-Reply-To: <20110519180626.GA16555@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2224 Lines: 70 2.6.38-stable review patch. If anyone has any objections, please let us know. ------------------ From: Ben Hutchings commit 9c412942a0bb19ba18f7bd939d42eff1e132a901 upstream. The USB protocol this driver implements appears to require 2 bytes of padding in front of each received packet. This used to be equal to the value of NET_IP_ALIGN on x86, so the driver abused that constant and mostly worked, but this is no longer the case. The driver also mixed up the URB and packet lengths, resulting in 2 bytes of junk at the end of the skb. Introduce a private constant for the 2 bytes of padding; fix this confusion and check for the under-length case. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/usb/ipheth.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -65,6 +65,7 @@ #define IPHETH_USBINTF_PROTO 1 #define IPHETH_BUF_SIZE 1516 +#define IPHETH_IP_ALIGN 2 /* padding at front of URB */ #define IPHETH_TX_TIMEOUT (5 * HZ) #define IPHETH_INTFNUM 2 @@ -202,18 +203,21 @@ static void ipheth_rcvbulk_callback(stru return; } - len = urb->actual_length; - buf = urb->transfer_buffer; + if (urb->actual_length <= IPHETH_IP_ALIGN) { + dev->net->stats.rx_length_errors++; + return; + } + len = urb->actual_length - IPHETH_IP_ALIGN; + buf = urb->transfer_buffer + IPHETH_IP_ALIGN; - skb = dev_alloc_skb(NET_IP_ALIGN + len); + skb = dev_alloc_skb(len); if (!skb) { err("%s: dev_alloc_skb: -ENOMEM", __func__); dev->net->stats.rx_dropped++; return; } - skb_reserve(skb, NET_IP_ALIGN); - memcpy(skb_put(skb, len), buf + NET_IP_ALIGN, len - NET_IP_ALIGN); + memcpy(skb_put(skb, len), buf, len); skb->dev = dev->net; skb->protocol = eth_type_trans(skb, dev->net); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/