From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756804AbaISGiN (ORCPT ); Fri, 19 Sep 2014 02:38:13 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40113 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751464AbaISGiM (ORCPT ); Fri, 19 Sep 2014 02:38:12 -0400 From: Jason Wang To: davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Jason Wang Subject: [PATCH net-next] net: keep original skb which only needs header checking during software GSO Date: Fri, 19 Sep 2014 14:38:06 +0800 Message-Id: <1411108686-20602-1-git-send-email-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit ce93718fb7cdbc064c3000ff59e4d3200bdfa744 ("net: Don't keep around original SKB when we software segment GSO frames") frees the original skb after software GSO even for dodgy gso skbs. This breaks the stream throughput from untrusted sources, since only header checking was done during software GSO instead of a true segmentation. This patch fixes this by freeing the original gso skb only when it was really segmented by software. Fixes ce93718fb7cdbc064c3000ff59e4d3200bdfa744 ("net: Don't keep around original SKB when we software segment GSO frames.") CC: David S. Miller Signed-off-by: Jason Wang --- net/core/dev.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index e916ba8..b7a0e1d 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2694,10 +2694,12 @@ struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev) struct sk_buff *segs; segs = skb_gso_segment(skb, features); - kfree_skb(skb); if (IS_ERR(segs)) segs = NULL; - skb = segs; + else if (segs) { + kfree_skb(skb); + skb = segs; + } } else { if (skb_needs_linearize(skb, features) && __skb_linearize(skb)) -- 1.9.1