ip6_output: do skb ufo init for peeked non ufo skb as well

Now, if user application does:
sendto len<mtu flag MSG_MORE
sendto len>mtu flag 0
The skb is not treated as fragmented one because it is not initialized
that way. So move the initialization to fix this.

introduced by:
commit e89e9cf539a28df7d0eb1d0a545368e9920b34ac "[IPv4/IPv6]: UFO Scatter-gather approach"

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 11 deletions

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index a54c45ce4a48..975624b8d2ea 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1008,6 +1008,7 @@ static inline int ip6_ufo_append_data(struct sock *sk,
 
 {
         struct sk_buff *skb;
+        struct frag_hdr fhdr;
         int err;
 
         /* There is support for UDP large send offload by network
@@ -1015,8 +1016,6 @@ static inline int ip6_ufo_append_data(struct sock *sk,
          * udp datagram
          */
         if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
-                struct frag_hdr fhdr;
-
                 skb = sock_alloc_send_skb(sk,
                         hh_len + fragheaderlen + transhdrlen + 20,
                         (flags & MSG_DONTWAIT), &err);
@@ -1036,20 +1035,24 @@ static inline int ip6_ufo_append_data(struct sock *sk,
                 skb->transport_header = skb->network_header + fragheaderlen;
 
                 skb->protocol = htons(ETH_P_IPV6);
-                skb->ip_summed = CHECKSUM_PARTIAL;
                 skb->csum = 0;
 
-                /* Specify the length of each IPv6 datagram fragment.
-                 * It has to be a multiple of 8.
-                 */
-                skb_shinfo(skb)->gso_size = (mtu - fragheaderlen -
-                                             sizeof(struct frag_hdr)) & ~7;
-                skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
-                ipv6_select_ident(&fhdr, rt);
-                skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
                 __skb_queue_tail(&sk->sk_write_queue, skb);
+        } else if (skb_is_gso(skb)) {
+                goto append;
         }
 
+        skb->ip_summed = CHECKSUM_PARTIAL;
+        /* Specify the length of each IPv6 datagram fragment.
+         * It has to be a multiple of 8.
+         */
+        skb_shinfo(skb)->gso_size = (mtu - fragheaderlen -
+                                     sizeof(struct frag_hdr)) & ~7;
+        skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
+        ipv6_select_ident(&fhdr, rt);
+        skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
+
+append:
         return skb_append_datato_frags(sk, skb, getfrag, from,
                                        (length - transhdrlen));
 }