zebra: prefer outer label_type for recursive nexthops

When resolving a recursive nexthop, prefer the "outer"
label type, if present.

Signed-off-by: Mark Stapp <mjs@voltanet.io>

diff --git a/zebra/zebra_nhg.c b/zebra/zebra_nhg.c
index f24552c80bd6b4b6a8a4b9920e9a6e627b8849f0..a656002fc76e7b272cb5508251182fba3fc17dc5 100644 (file)
--- a/zebra/zebra_nhg.c
+++ b/zebra/zebra_nhg.c
@@ -1681,17 +1681,37 @@ static void nexthop_set_resolved(afi_t afi, const struct nexthop *newhop,
 
        /* Copy labels of the resolved route and the parent resolving to it */
        if (newhop->nh_label) {
-               for (i = 0; i < newhop->nh_label->num_labels; i++)
+               for (i = 0; i < newhop->nh_label->num_labels; i++) {
+                       /* Be a bit picky about overrunning the local array */
+                       if (num_labels >= MPLS_MAX_LABELS) {
+                               if (IS_ZEBRA_DEBUG_NHG || IS_ZEBRA_DEBUG_RIB)
+                                       zlog_debug("%s: too many labels in newhop %pNHv",
+                                                  __func__, newhop);
+                               break;
+                       }
                        labels[num_labels++] = newhop->nh_label->label[i];
+               }
+               /* Use the "outer" type */
                label_type = newhop->nh_label_type;
        }
 
        if (nexthop->nh_label) {
-               for (i = 0; i < nexthop->nh_label->num_labels; i++)
+               for (i = 0; i < nexthop->nh_label->num_labels; i++) {
+                       /* Be a bit picky about overrunning the local array */
+                       if (num_labels >= MPLS_MAX_LABELS) {
+                               if (IS_ZEBRA_DEBUG_NHG || IS_ZEBRA_DEBUG_RIB)
+                                       zlog_debug("%s: too many labels in nexthop %pNHv",
+                                                  __func__, nexthop);
+                               break;
+                       }
                        labels[num_labels++] = nexthop->nh_label->label[i];
+               }
 
-               /* If the parent has labels, use its type */
-               label_type = nexthop->nh_label_type;
+               /* If the parent has labels, use its type if
+                * we don't already have one.
+                */
+               if (label_type == ZEBRA_LSP_NONE)
+                       label_type = nexthop->nh_label_type;
        }
 
        if (num_labels)