From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966638AbbLPSPl (ORCPT ); Wed, 16 Dec 2015 13:15:41 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:49740 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966400AbbLPRkP (ORCPT ); Wed, 16 Dec 2015 12:40:15 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Daniel Borkmann , "David S. Miller" , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 039/128] packet: do skb_probe_transport_header when we actually have data Date: Wed, 16 Dec 2015 09:37:59 -0800 Message-Id: <1450287568-19808-40-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1450287568-19808-1-git-send-email-kamal@canonical.com> References: <1450287568-19808-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Borkmann commit efdfa2f7848f64517008136fb41f53c4a1faf93a upstream. In tpacket_fill_skb() commit c1aad275b029 ("packet: set transport header before doing xmit") and later on 40893fd0fd4e ("net: switch to use skb_probe_transport_header()") was probing for a transport header on the skb from a ring buffer slot, but at a time, where the skb has _not even_ been filled with data yet. So that call into the flow dissector is pretty useless. Lets do it after we've set up the skb frags. Fixes: c1aad275b029 ("packet: set transport header before doing xmit") Reported-by: Eric Dumazet Signed-off-by: Daniel Borkmann Acked-by: Jason Wang Signed-off-by: David S. Miller Signed-off-by: Kamal Mostafa --- net/packet/af_packet.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ca5c040..aab5c0a 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2132,8 +2132,6 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, skb_reserve(skb, hlen); skb_reset_network_header(skb); - if (!packet_use_direct_xmit(po)) - skb_probe_transport_header(skb, 0); if (unlikely(po->tp_tx_has_off)) { int off_min, off_max, off; off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll); @@ -2213,6 +2211,9 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, len = ((to_write > len_max) ? len_max : to_write); } + if (!packet_use_direct_xmit(po)) + skb_probe_transport_header(skb, 0); + return tp_len; } -- 1.9.1