sctp: move skb_dst_set() a bit downwards in sctp_packet_transmit()

skb_dst_set will use dst, if dst is NULL although is not a problem,
then goto the 'no_route' and free nskb, so do the skb_dst_set is pointless.
so move the skb_dst_set after dst check.
Remove the unnecessary initialization as well.

v2: fix the subject line because it would confuse people,
    as pointed out by Daniel.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sctp/output.c b/net/sctp/output.c
index b971cd226cf5518619e55bf8e8ccc1b933dcc1bc..0f4d15fc2627bcccb546ee2da883f812daa4e4a1 100644 (file)
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -387,7 +387,7 @@ int sctp_packet_transmit(struct sctp_packet *packet)
        int err = 0;
        int padding;            /* How much padding do we need?  */
        __u8 has_data = 0;
-       struct dst_entry *dst = tp->dst;
+       struct dst_entry *dst;
        unsigned char *auth = NULL;     /* pointer to auth in skb data */
 
        pr_debug("%s: packet:%p\n", __func__, packet);
@@ -420,9 +420,9 @@ int sctp_packet_transmit(struct sctp_packet *packet)
                }
        }
        dst = dst_clone(tp->dst);
-       skb_dst_set(nskb, dst);
        if (!dst)
                goto no_route;
+       skb_dst_set(nskb, dst);
 
        /* Build the SCTP header.  */
        sh = (struct sctphdr *)skb_push(nskb, sizeof(struct sctphdr));