From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755352Ab1ABHzt (ORCPT ); Sun, 2 Jan 2011 02:55:49 -0500 Received: from mail.windriver.com ([147.11.1.11]:35421 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753650Ab1ABHXQ (ORCPT ); Sun, 2 Jan 2011 02:23:16 -0500 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Jarek Poplawski , Eric Dumazet , "David S. Miller" , Paul Gortmaker Subject: [34-longterm 111/260] gro: Re-fix different skb headrooms Date: Sun, 2 Jan 2011 02:16:47 -0500 Message-Id: <1293952756-15010-112-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.3.3 In-Reply-To: <1293952756-15010-1-git-send-email-paul.gortmaker@windriver.com> References: <1293952756-15010-1-git-send-email-paul.gortmaker@windriver.com> X-OriginalArrivalTime: 02 Jan 2011 07:22:11.0430 (UTC) FILETIME=[C5957060:01CBAA4D] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jarek Poplawski commit 64289c8e6851bca0e589e064c9a5c9fbd6ae5dd4 upstream. The patch: "gro: fix different skb headrooms" in its part: "2) allocate a minimal skb for head of frag_list" is buggy. The copied skb has p->data set at the ip header at the moment, and skb_gro_offset is the length of ip + tcp headers. So, after the change the length of mac header is skipped. Later skb_set_mac_header() sets it into the NET_SKB_PAD area (if it's long enough) and ip header is misaligned at NET_SKB_PAD + NET_IP_ALIGN offset. There is no reason to assume the original skb was wrongly allocated, so let's copy it as it was. bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=16626 fixes commit: 3d3be4333fdf6faa080947b331a6a19bce1a4f57 Reported-by: Plamen Petrov Signed-off-by: Jarek Poplawski CC: Eric Dumazet Acked-by: Eric Dumazet Tested-by: Plamen Petrov Signed-off-by: David S. Miller Signed-off-by: Paul Gortmaker --- net/core/skbuff.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index c1c86f5..9e7214e 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2711,7 +2711,7 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) } else if (skb_gro_len(p) != pinfo->gso_size) return -E2BIG; - headroom = NET_SKB_PAD + NET_IP_ALIGN; + headroom = skb_headroom(p); nskb = alloc_skb(headroom + skb_gro_offset(p), GFP_ATOMIC); if (unlikely(!nskb)) return -ENOMEM; -- 1.7.3.3