nhrp: fix race condition

where null lladdr recieved from zebra before nhrp next hop is installed. Signed-off-by: Lou Berger <[email protected]>
FRRouting · Feb 7, 2024 · 5d9ebe6 · 5d9ebe6
1 parent 1bc2fa3
commit 5d9ebe6
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/nhrpd/netlink_arp.c b/nhrpd/netlink_arp.c
@@ -191,6 +191,11 @@ int nhrp_neighbor_operation(ZAPI_CALLBACK_ARGS)
 			       "Netlink: update binding for %pSU dev %s from c %pSU peer.vc.nbma %pSU to lladdr %pSU",
 			       &addr, ifp->name, &c->cur.remote_nbma_natoa,
 			       &c->cur.peer->vc->remote.nbma, &lladdr);
+
+			if (lladdr.sa.sa_family == AF_UNSPEC)
+				/* nothing from zebra, so use nhrp peer */
+				lladdr = c->cur.peer->vc->remote.nbma;
+
 			/* In case of shortcuts, nbma is given by lladdr, not
 			 * vc->remote.nbma.
 			 */