tcp: handle multiple syns in time-wait

If multiple syns are received in one dispatch for the same time-wait
connection, the first removes the connection while subsequent packets
either lookup a nonexistent or an unrelated connection.

Avoid the former with a check.

Type: fix

Change-Id: Ia5f1b3bbd568566eaf36121206aa12363a15b418
Signed-off-by: Florin Coras <[email protected]>

diff --git a/src/vnet/tcp/tcp_input.c b/src/vnet/tcp/tcp_input.c
index 70b5d28..cd3e4b7 100644 (file)
--- a/src/vnet/tcp/tcp_input.c
+++ b/src/vnet/tcp/tcp_input.c
@@ -2551,7 +2551,7 @@ tcp46_listen_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
          tcp_connection_t *tc;
          tc = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
                                   thread_index);
-         if (tc->state != TCP_STATE_TIME_WAIT)
+         if (!tc || tc->state != TCP_STATE_TIME_WAIT)
            {
              tcp_inc_counter (listen, TCP_ERROR_CREATE_EXISTS, 1);
              goto done;