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From:
Claudio Jeker <cjeker@diehard.n-r-g.com>
Subject:
bgpd: fix add-path send best plus 5
To:
tech@openbsd.org
Date:
Tue, 14 Jan 2025 11:08:54 +0100

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I broke add-path send when I partially killed the PREFIX_FLAG_STALE flag.
add-path uses this flag to temporarily mark the routes in the adj-rib-out
as stale and then after updating the routes it walks the list again and
withdraws the routes that have the flag still set.

Removing the PREFIX_FLAG_STALE clearing in one of the prefix_adjout_update
cases broke the method above. While not really needed I readded the same
clearing in prefix_adjout_withdraw().

With this 'announce add-path send best plus 5' works again as expected.
-- 
:wq Claudio

Index: rde_rib.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde_rib.c,v
diff -u -p -r1.266 rde_rib.c
--- rde_rib.c	12 Dec 2024 20:19:03 -0000	1.266
+++ rde_rib.c	13 Jan 2025 19:54:39 -0000
@@ -1273,6 +1273,7 @@ prefix_adjout_update(struct prefix *p, s
 			/* nothing changed */
 			p->validation_state = state->vstate;
 			p->lastchange = getmonotime();
+			p->flags &= ~PREFIX_FLAG_STALE;
 			return;
 		}
 
@@ -1343,6 +1344,7 @@ prefix_adjout_withdraw(struct prefix *p)
 	/* already a withdraw, shortcut */
 	if (p->flags & PREFIX_FLAG_WITHDRAW) {
 		p->lastchange = getmonotime();
+		p->flags &= ~PREFIX_FLAG_STALE;
 		return;
 	}
 	/* pending update just got withdrawn */