Fix vpp crash sending arp or probing neighb (VPP-917)

VPP crash when trying to send arp message or to probe neighbor over
interface with IP address but without hw address (local0 and tunnels
- vxlan, gre, ...)

Change-Id: I08a1c97d3ea913fc11b2886cf73b2ccc31356664
Signed-off-by: Pavel Kotucek <pkotucek@cisco.com>

2 files changed, 29 insertions, 0 deletions

diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c
index 4b05bf10c75..ee17ea8804e 100755
--- a/src/vnet/ip/ip4_forward.c
+++ b/src/vnet/ip/ip4_forward.c
@@ -898,6 +898,13 @@ ip4_add_del_interface_address_internal (vlib_main_t * vm,
   u32 if_address_index, elts_before;
   ip4_address_fib_t ip4_af, *addr_fib = 0;
 
+  /* local0 interface doesn't support IP addressing  */
+  if (sw_if_index == 0)
+    {
+      return
+       clib_error_create ("local0 interface doesn't support IP addressing");
+    }
+
   vec_validate (im->fib_index_by_sw_if_index, sw_if_index);
   ip4_addr_fib_init (&ip4_af, address,
 		     vec_elt (im->fib_index_by_sw_if_index, sw_if_index));
@@ -2319,6 +2326,13 @@ ip4_probe_neighbor (vlib_main_t * vm, ip4_address_t * dst, u32 sw_if_index)
 				       &bi);
 
   hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
+  if (PREDICT_FALSE (!hi->hw_address))
+    {
+      return clib_error_return (0, "%U: interface %U do not support ip probe",
+				format_ip4_address, dst,
+				format_vnet_sw_if_index_name, vnm,
+				sw_if_index);
+    }
 
   clib_memcpy (h->ip4_over_ethernet[0].ethernet, hi->hw_address,
 	       sizeof (h->ip4_over_ethernet[0].ethernet));
diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c
index 604e14924f9..bc66416e5ef 100644
--- a/src/vnet/ip/ip6_forward.c
+++ b/src/vnet/ip/ip6_forward.c
@@ -481,6 +481,13 @@ ip6_add_del_interface_address (vlib_main_t * vm,
   u32 if_address_index;
   ip6_address_fib_t ip6_af, *addr_fib = 0;
 
+  /* local0 interface doesn't support IP addressing */
+  if (sw_if_index == 0)
+    {
+      return
+	clib_error_create ("local0 interface doesn't support IP addressing");
+    }
+
   vec_validate (im->fib_index_by_sw_if_index, sw_if_index);
   vec_validate (im->mfib_index_by_sw_if_index, sw_if_index);
 
@@ -1918,6 +1925,14 @@ ip6_probe_neighbor (vlib_main_t * vm, ip6_address_t * dst, u32 sw_if_index)
   h->ip.src_address = src[0];
   h->neighbor.target_address = dst[0];
 
+  if (PREDICT_FALSE (!hi->hw_address))
+    {
+      return clib_error_return (0, "%U: interface %U do not support ip probe",
+				format_ip6_address, dst,
+				format_vnet_sw_if_index_name, vnm,
+				sw_if_index);
+    }
+
   clib_memcpy (h->link_layer_option.ethernet_address, hi->hw_address,
 	       vec_len (hi->hw_address));