zebra: Prevent protodown_rc from going Bzonkas

The code that handles the protodown_rc setting for
VRRP interfaces in zebra is sending a interface
to be set into a protodown state *before* the
interface has been learned by the kernel.  Resulting
in crashes when the data plane sends the ctx back
to us saying hey man you are uncool.

Additionally change the protodown code to refuse
to send any protodown_rc codes *until* the interface
has actually been learned about from the kernel.

Ticket: 3582375
Signed-off-by: Donald Sharp <sharpd@nvidia.com>

diff --git a/zebra/interface.c b/zebra/interface.c
index 90787f3aa03a9b5b045428cd6027751752319943..9ca330571f4dff7fd6beb0e79d5e63a759f7bf61 100644 (file)
--- a/zebra/interface.c
+++ b/zebra/interface.c
@@ -1195,6 +1195,12 @@ static bool if_ignore_set_protodown(const struct interface *ifp, bool new_down,
 
        zif = ifp->info;
 
+       /*
+        * FRR does not have enough data to make this request
+        */
+       if (ifp->ifindex == IFINDEX_INTERNAL)
+               return true;
+
        /* Current state as we know it */
        old_down = !!(ZEBRA_IF_IS_PROTODOWN(zif));
        old_set_down = !!CHECK_FLAG(zif->flags, ZIF_FLAG_SET_PROTODOWN);