| From | Luis Henriques <> | Subject | [PATCH 3.16.y-ckt 029/126] packet: do skb_probe_transport_header when we actually have data | Date | Wed, 6 Jan 2016 10:35:58 +0000 |
| |
3.16.7-ckt22 -stable review patch. If anyone has any objections, please let me know.
------------------
From: Daniel Borkmann <daniel@iogearbox.net>
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 <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: Luis Henriques <luis.henriques@canonical.com> --- 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 1f618bbce0ac..fc94622f755c 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2127,8 +2127,6 @@ 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); @@ -2212,6 +2210,9 @@ 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; }
|