bgpd: use on stack struct attr_extra in bgp_update_receive()

Reduce memory heap fragmentation and pressure on the memory allocator.

Signed-off-by: Jorge Boncompte [DTI2] <jorge@dti2.net>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c
index 95ed804..cfa0b57 100644
--- a/bgpd/bgp_packet.c
+++ b/bgpd/bgp_packet.c
@@ -1519,6 +1519,7 @@
   u_char *end;
   struct stream *s;
   struct attr attr;
+  struct attr_extra extra;
   bgp_size_t attribute_len;
   bgp_size_t update_len;
   bgp_size_t withdraw_len;
@@ -1538,10 +1539,12 @@
 
   /* Set initial values. */
   memset (&attr, 0, sizeof (struct attr));
+  memset (&extra, 0, sizeof (struct attr_extra));
   memset (&update, 0, sizeof (struct bgp_nlri));
   memset (&withdraw, 0, sizeof (struct bgp_nlri));
   memset (&mp_update, 0, sizeof (struct bgp_nlri));
   memset (&mp_withdraw, 0, sizeof (struct bgp_nlri));
+  attr.extra = &extra;
 
   s = peer->ibuf;
   end = stream_pnt (s) + size;
@@ -1669,8 +1672,6 @@
       if (ret < 0)
         {
           bgp_attr_unintern_sub (&attr);
-          if (attr.extra)
-            bgp_attr_extra_free (&attr);
 	  return -1;
 	}
 
@@ -1697,8 +1698,6 @@
 	  if (ret < 0)
 	    {
 	      bgp_attr_unintern_sub (&attr);
-              if (attr.extra)
-                bgp_attr_extra_free (&attr);
 	      return -1;
             }
 
@@ -1845,9 +1844,7 @@
   /* Everything is done.  We unintern temporary structures which
      interned in bgp_attr_parse(). */
   bgp_attr_unintern_sub (&attr);
-  if (attr.extra)
-    bgp_attr_extra_free (&attr);
-  
+
   /* If peering is stopped due to some reason, do not generate BGP
      event.  */
   if (peer->status != Established)