lkml.org 
[lkml]   [2016]   [Jan]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.12 06/91] packet: do skb_probe_transport_header when we actually have data
Date
From: Daniel Borkmann <daniel@iogearbox.net>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

[ Upstream commit efdfa2f7848f64517008136fb41f53c4a1faf93a ]

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 <edumazet@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
net/packet/af_packet.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 7f63613148b9..645010b9abc0 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1991,7 +1991,6 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,

skb_reserve(skb, hlen);
skb_reset_network_header(skb);
- skb_probe_transport_header(skb, 0);

if (po->tp_tx_has_off) {
int off_min, off_max, off;
@@ -2076,6 +2075,8 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
len = ((to_write > len_max) ? len_max : to_write);
}

+ skb_probe_transport_header(skb, 0);
+
return tp_len;
}

--
2.6.4


\
 
 \ /
  Last update: 2016-01-05 20:01    [W:0.549 / U:0.136 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site