From de5c01280ed40274e02c6f2ed7ef13c49d7f9762 Mon Sep 17 00:00:00 2001
From: Pim van Pelt <pim@ipng.nl>
Date: Thu, 12 Aug 2021 12:58:31 +0200
Subject: [PATCH] Refuse to create an LCP for sub-interfaces that does not have
 exact-match set

---
 lcpng_interface.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lcpng_interface.c b/lcpng_interface.c
index 5edc7a3..033c0b3 100644
--- a/lcpng_interface.c
+++ b/lcpng_interface.c
@@ -655,6 +655,11 @@ lcp_itf_pair_create (u32 phy_sw_if_index, u8 *host_if_name,
       u16 outer_vlan, inner_vlan;
       u16 outer_proto, inner_proto;
 
+      if (sw->type == VNET_SW_INTERFACE_TYPE_SUB && sw->sub.eth.flags.exact_match == 0) {
+        LCP_ITF_PAIR_ERR ("pair_create: can't create LCP for a sub-interface without exact-match set");
+        return VNET_API_ERROR_INVALID_ARGUMENT;
+      }
+
       /*
        * Find the parent tap by finding the pair from the parent phy
        */