Lua: Fix add and remove Fields when reload Lua plugins

Reset wslua_dfilter and remove the Field tap_listener when
reloading plugins.

Check for tap listeners in rescan_packets() after ws_epan_new()
because Lua may register the Lua field tap when adding Fields.

Bug: 12328
Change-Id: Ibbd8339033132c6f3b61d7e9c9ced9ed2b9affec
Reviewed-on: https://code.wireshark.org/review/14871
Petri-Dish: Stig Bjørlykke <stig@bjorlykke.org>
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Stig Bjørlykke <stig@bjorlykke.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/file.c b/file.c
index a0c21b2ddb..04fd8becc9 100644
--- a/file.c
+++ b/file.c
@@ -1630,6 +1630,12 @@ rescan_packets(capture_file *cf, const char *action, const char *action_item, gb
     cf->epan = ws_epan_new(cf);
     cf->cinfo.epan = cf->epan;
 
+    /* A new Lua tap listener may be registered in lua_prime_all_fields()
+       called via epan_new() / init_dissection() when reloading Lua plugins. */
+    if (!create_proto_tree && have_filtering_tap_listeners()) {
+      create_proto_tree = TRUE;
+    }
+
     /* We need to redissect the packets so we have to discard our old
      * packet list store. */
     packet_list_clear();