sctp: call sk_setup_caps in sctp_packet_transmit instead

sk_setup_caps() was originally called in Commit 90017accff61 ("sctp:
Add GSO support"), as:

  "We have to refresh this in case we are xmiting to more than one
   transport at a time"

This actually happens in the loop of sctp_outq_flush_transports(),
and it shouldn't be tied to gso, so move it out of gso part and
before sctp_packet_pack().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/sctp/output.c b/net/sctp/output.c
index 1441eaf..fb16500 100644 (file)
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -508,12 +508,6 @@ merge:
                                        sizeof(struct inet6_skb_parm)));
                skb_shinfo(head)->gso_segs = pkt_count;
                skb_shinfo(head)->gso_size = GSO_BY_FRAGS;
-               rcu_read_lock();
-               if (skb_dst(head) != tp->dst) {
-                       dst_hold(tp->dst);
-                       sk_setup_caps(sk, tp->dst);
-               }
-               rcu_read_unlock();
                goto chksum;
        }
 
@@ -593,6 +587,13 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
        }
        skb_dst_set(head, dst);
 
+       rcu_read_lock();
+       if (__sk_dst_get(sk) != tp->dst) {
+               dst_hold(tp->dst);
+               sk_setup_caps(sk, tp->dst);
+       }
+       rcu_read_unlock();
+
        /* pack up chunks */
        pkt_count = sctp_packet_pack(packet, head, gso, gfp);
        if (!pkt_count) {