in-band: Fix null pointer dereference.

Triggering this would require deleting the in-use datapath at just the
right time, but we still don't want it to happen.

diff --git a/ofproto/in-band.c b/ofproto/in-band.c
index 94024bc..adf89d1 100644 (file)
--- a/ofproto/in-band.c
+++ b/ofproto/in-band.c
@@ -410,7 +410,7 @@ in_band_msg_in_hook(struct in_band *in_band, const flow_t *flow,
         }
 
         local_mac = get_local_mac(in_band);
-        if (eth_addr_equals(dhcp->chaddr, local_mac)) {
+        if (local_mac && eth_addr_equals(dhcp->chaddr, local_mac)) {
             return true;
         }
     }