Bug#24478 DROP TRIGGER is not caught by replicate-*-table filters

Problem: DROP TRIGGER was not properly handled in combination
with slave filters, which made replication stop
Fix: loading table name before checking slave filters when
dropping a trigger.

3 files changed, 30 insertions, 5 deletions

diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index b0b7afc6528..7226a8e3c86 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -33,6 +33,7 @@
 #include "sp_head.h"
 #include "sp.h"
 #include "sp_cache.h"
+#include "sql_trigger.h"
 
 #ifdef HAVE_OPENSSL
 /*
@@ -2485,6 +2486,30 @@ mysql_execute_command(THD *thd)
 #ifdef HAVE_REPLICATION
   if (unlikely(thd->slave_thread))
   {
+    if (lex->sql_command == SQLCOM_DROP_TRIGGER)
+    {
+      /*
+        When dropping a trigger, we need to load its table name
+        before checking slave filter rules.
+      */
+      add_table_for_trigger(thd, thd->lex->spname, 1, &all_tables);
+      
+      if (!all_tables)
+      {
+        /*
+          If table name cannot be loaded,
+          it means the trigger does not exists possibly because
+          CREATE TRIGGER was previously skipped for this trigger
+          according to slave filtering rules.
+          Returning success without producing any errors in this case.
+        */
+        DBUG_RETURN(0);
+      }
+      
+      // force searching in slave.cc:tables_ok() 
+      all_tables->updating= 1;
+    }
+    
     /*
       Check if statment should be skipped because of slave filtering
       rules
diff --git a/sql/sql_trigger.cc b/sql/sql_trigger.cc
index 3569733d064..0b648570b86 100644
--- a/sql/sql_trigger.cc
+++ b/sql/sql_trigger.cc
@@ -107,10 +107,6 @@ const LEX_STRING trg_event_type_names[]=
 };
 
 
-static int
-add_table_for_trigger(THD *thd, sp_name *trig, bool if_exists,
-                      TABLE_LIST ** table);
-
 class Handle_old_incorrect_sql_modes_hook: public Unknown_key_hook
 {
 private:
@@ -1183,7 +1179,7 @@ bool Table_triggers_list::get_trigger_info(THD *thd, trg_event_type event,
     1 Error
 */
 
-static int
+int
 add_table_for_trigger(THD *thd, sp_name *trig, bool if_exists,
                       TABLE_LIST **table)
 {
diff --git a/sql/sql_trigger.h b/sql/sql_trigger.h
index 7e0fadfa677..8970986b931 100644
--- a/sql/sql_trigger.h
+++ b/sql/sql_trigger.h
@@ -139,3 +139,7 @@ private:
 
 extern const LEX_STRING trg_action_time_type_names[];
 extern const LEX_STRING trg_event_type_names[];
+
+int
+add_table_for_trigger(THD *thd, sp_name *trig, bool if_exists,
+                      TABLE_LIST **table);