From: Maria Matejka <mq@ucw.cz>
Date: Tue, 22 Mar 2022 13:39:32 +0000 (+0100)
Subject: BGP: Fixed LLGR depreferencing in bgp_rte_mergable
X-Git-Tag: v2.0.11~48
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dabd7bccb3b9e2b7482cf4ae7619a67559f3ac94;p=thirdparty%2Fbird.git

BGP: Fixed LLGR depreferencing in bgp_rte_mergable
---

diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index 454686cf3..a7c49be59 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -2074,14 +2074,17 @@ bgp_rte_mergable(rte *pri, rte *sec)
   u32 p, s;
 
   /* Skip suppressed routes (see bgp_rte_recalculate()) */
-  /* LLGR draft - depreference stale routes */
-  if (pri->pflags != sec->pflags)
+  if ((pri->pflags ^ sec->pflags) & BGP_REF_SUPPRESSED)
     return 0;
 
   /* RFC 4271 9.1.2.1. Route resolvability test */
   if (rte_resolvable(pri) != rte_resolvable(sec))
     return 0;
 
+  /* LLGR draft - depreference stale routes */
+  if (rte_stale(pri) != rte_stale(sec))
+    return 0;
+
   /* Start with local preferences */
   x = ea_find(pri->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_LOCAL_PREF));
   y = ea_find(sec->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_LOCAL_PREF));