From dcd607718385d02ce3741de225927a57f528f93b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 7 Nov 2013 18:32:06 -0800 Subject: [PATCH 1/1] inet: fix a UFO regression While testing virtio_net and skb_segment() changes, Hannes reported that UFO was sending wrong frames. It appears this was introduced by a recent commit : 8c3a897bfab1 ("inet: restore gso for vxlan") The old condition to perform IP frag was : tunnel = !!skb->encapsulation; ... if (!tunnel && proto == IPPROTO_UDP) { So the new one should be : udpfrag = !skb->encapsulation && proto == IPPROTO_UDP; ... if (udpfrag) { Initialization of udpfrag must be done before call to ops->callbacks.gso_segment(skb, features), as skb_udp_tunnel_segment() clears skb->encapsulation (We want udpfrag to be true for UFO, false for VXLAN) With help from Alexei Starovoitov Reported-by: Hannes Frederic Sowa Signed-off-by: Eric Dumazet Cc: Alexei Starovoitov Signed-off-by: David S. Miller --- net/ipv4/af_inet.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 09d78d4a3cf..68af9aac91d 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1299,6 +1299,9 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, segs = ERR_PTR(-EPROTONOSUPPORT); + /* Note : following gso_segment() might change skb->encapsulation */ + udpfrag = !skb->encapsulation && proto == IPPROTO_UDP; + ops = rcu_dereference(inet_offloads[proto]); if (likely(ops && ops->callbacks.gso_segment)) segs = ops->callbacks.gso_segment(skb, features); @@ -1306,7 +1309,6 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, if (IS_ERR_OR_NULL(segs)) goto out; - udpfrag = !!skb->encapsulation && proto == IPPROTO_UDP; skb = segs; do { iph = (struct iphdr *)(skb_mac_header(skb) + nhoff); -- 2.43.2