devices: VPP crash when doing packet trace dump

VPP recycles the graph node index when the interface is deleted. Most tx graph
nodes have format_tx_function. tapcli does not. If tapcli happens to
recycle a tx graph node index which has format_tx_function, problem will arise
when showing the trace buffer which was collected for the node index that
tapcli recycles.

The fix is nothing fantasy, just add a format_tx_trace function which
does nothing in case it it called. tapcli is deprecated in 19.04. There is
no need to cherrypick this to later releases.

Type: fix
Ticket: VPP-1742

Signed-off-by: Steven Luong <[email protected]>
Change-Id: I010b3f35e59a474cb134a8b1bc718c242e3aa93c

diff --git a/src/vnet/unix/tapcli.c b/src/vnet/unix/tapcli.c
index b4df8e8..81725a9 100644 (file)
--- a/src/vnet/unix/tapcli.c
+++ b/src/vnet/unix/tapcli.c
@@ -753,6 +753,13 @@ tapcli_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
   return 0;
 }
 
+u8 *
+format_tapcli_tx_trace (u8 * s, va_list * va)
+{
+  s = format (s, "tapcli tx trace is not supported");
+  return s;
+}
+
 /* *INDENT-OFF* */
 VNET_DEVICE_CLASS (tapcli_dev_class,static) = {
   .name = "tapcli",
@@ -761,6 +768,7 @@ VNET_DEVICE_CLASS (tapcli_dev_class,static) = {
   .rx_redirect_to_node = tapcli_set_interface_next_node,
   .name_renumber = tap_name_renumber,
   .admin_up_down_function = tapcli_interface_admin_up_down,
+  .format_tx_trace = format_tapcli_tx_trace,
 };
 /* *INDENT-ON* */