[X25]: Add missing x25_neigh_put

The function x25_get_neigh increments a reference count. At the point of
the second goto out, the result of calling x25_get_neigh is only stored in
a local variable, and thus no one outside the function will be able to
decrease the reference count. Thus, x25_neigh_put should be called before
the return in this case.

The problem was found using the following semantic match.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>

@@
type T,T1,T2;
identifier E;
statement S;
expression x1,x2,x3;
int ret;
@@

T E;
...
* if ((E = x25_get_neigh(...)) == NULL)
S
... when != x25_neigh_put(...,(T1)E,...)
when != if (E != NULL) { ... x25_neigh_put(...,(T1)E,...); ...}
when != x1 = (T1)E
when != E = x3;
when any
if (...) {
... when != x25_neigh_put(...,(T2)E,...)
when != if (E != NULL) { ... x25_neigh_put(...,(T2)E,...); ...}
when != x2 = (T2)E
(
* return;
|
* return ret;
)
}
// </smpl>

Signed-off-by: Julia Lawall <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/x25/x25_forward.c

···
 		goto out;
 
 	if ( (skbn = pskb_copy(skb, GFP_ATOMIC)) == NULL){
-		goto out;
+		goto output;
 
 	}
 	x25_transmit_link(skbn, nb);
 
-	x25_neigh_put(nb);
 	rc = 1;
+output:
+	x25_neigh_put(nb);
 out:
 	return rc;
 }