pg: icmp4 & tcp4 ip length issue

[vpp.git] / src / vnet / ip / icmp4.c

diff --git a/src/vnet/ip/icmp4.c b/src/vnet/ip/icmp4.c
index 3626e96..a598ca9 100644 (file)
--- a/src/vnet/ip/icmp4.c
+++ b/src/vnet/ip/icmp4.c
@@ -653,7 +653,13 @@ icmp4_pg_edit_function (pg_main_t * pg,
       ASSERT (p0->current_data == 0);
       ip0 = (void *) (p0->data + ip_offset);
       icmp0 = (void *) (p0->data + icmp_offset);
-      len0 = clib_net_to_host_u16 (ip0->length) - ip4_header_bytes (ip0);
+
+      /* if IP length has been specified, then calculate the length based on buffer */
+      if (ip0->length == 0)
+       len0 = vlib_buffer_length_in_chain (vm, p0) - icmp_offset;
+      else
+       len0 = clib_net_to_host_u16 (ip0->length) - icmp_offset;
+
       icmp0->checksum =
        ~ip_csum_fold (ip_incremental_checksum (0, icmp0, len0));
     }