bgpd: Ignore stale entry candidates during bestpath selection.
During best path selection, if one of the candidates is a stale entry, do not
perform the neighbor address comparison as that information is invalid for
the stale entry. Attempting to perform the comparison results in a bgpd
exception.
Signed-off-by: Vivek Venkataraman <vivek@cumulusnetworks.com>
Reviewed-by: Dinesh G Dutt <ddutt@cumulusnetworks.com>
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index 34ba1ab..648dc9c 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -524,7 +524,11 @@
return 0;
}
- /* 11. Rourter-ID comparision. */
+ /* 11. Router-ID comparision. */
+ /* If one of the paths is "stale", the corresponding peer router-id will
+ * be 0 and would always win over the other path. If originator id is
+ * used for the comparision, it will decide which path is better.
+ */
if (newattr->flag & ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID))
new_id.s_addr = newattre->originator_id.s_addr;
else
@@ -553,6 +557,14 @@
return 0;
/* 13. Neighbor address comparision. */
+ /* Do this only if neither path is "stale" as stale paths do not have
+ * valid peer information (as the connection may or may not be up).
+ */
+ if (CHECK_FLAG (exist->flags, BGP_INFO_STALE))
+ return 1;
+ if (CHECK_FLAG (new->flags, BGP_INFO_STALE))
+ return 0;
+
ret = sockunion_cmp (new->peer->su_remote, exist->peer->su_remote);
if (ret == 1)