isisd: Uninstall routes only if installed

In some cases, IS-IS may attempt to remove routes that have not been
installed before. We can prevent IS-IS from doing this by aborting
`isis_zebra_route_del_route` when the ISIS_ROUTE_FLAG_ZEBRA_SYNCED flag
is unset, meaning that the route is not installed in the kernel.

Signed-off-by: Carmine Scarpitta <carmine.scarpitta@uniroma2.it>

diff --git a/isisd/isis_zebra.c b/isisd/isis_zebra.c
index 4813173f453b2a0ad936fd03257a36d287d12116..1706d27a3a0b0a89db93a94ceb173e035235860b 100644 (file)
--- a/isisd/isis_zebra.c
+++ b/isisd/isis_zebra.c
@@ -308,6 +308,9 @@ void isis_zebra_route_del_route(struct isis *isis,
        if (zclient->sock < 0)
                return;
 
+       if (!CHECK_FLAG(route_info->flag, ISIS_ROUTE_FLAG_ZEBRA_SYNCED))
+               return;
+
        memset(&api, 0, sizeof(api));
        api.vrf_id = isis->vrf_id;
        api.type = PROTO_TYPE;