From: Daniel Borkmann Date: Wed, 11 Nov 2015 22:25:41 +0000 (+0100) Subject: packet: always probe for transport header X-Git-Tag: v3.14.59~44 X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c8f0bbc005b28c860daaa797838374367cd2edab;p=linux packet: always probe for transport header [ Upstream commit 8fd6c80d9dd938ca338c70698533a7e304752846 ] We concluded that the skb_probe_transport_header() should better be called unconditionally. Avoiding the call into the flow dissector has also not really much to do with the direct xmit mode. While it seems that only virtio_net code makes use of GSO from non RX/TX ring packet socket paths, we should probe for a transport header nevertheless before they hit devices. Reference: http://thread.gmane.org/gmane.linux.network/386173/ Signed-off-by: Daniel Borkmann Acked-by: Jason Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index b36cf006b054..3feed4890944 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2210,8 +2210,7 @@ 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); + skb_probe_transport_header(skb, 0); return tp_len; } @@ -2538,8 +2537,8 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) len += vnet_hdr_len; } - if (!packet_use_direct_xmit(po)) - skb_probe_transport_header(skb, reserve); + skb_probe_transport_header(skb, reserve); + if (unlikely(extra_len == 4)) skb->no_fcs = 1;