MDEV-15444 Querying I_S.PARAMETERS can crash with a corrupted mysql.proc

1 files changed, 12 insertions, 0 deletions

diff --git a/sql/sp.h b/sql/sp.h
index d256814cb95..d35bb04069a 100644
--- a/sql/sp.h
+++ b/sql/sp.h
@@ -122,6 +122,16 @@ public:
   static const Sp_handler *handler(enum enum_sql_command cmd);
   static const Sp_handler *handler(stored_procedure_type type);
   static const Sp_handler *handler(MDL_key::enum_mdl_namespace ns);
+  /*
+    Return a handler only those SP objects that store
+    definitions in the mysql.proc system table
+  */
+  static const Sp_handler *handler_mysql_proc(stored_procedure_type type)
+  {
+    const Sp_handler *sph= handler(type);
+    return sph ? sph->sp_handler_mysql_proc() : NULL;
+  }
+
   static bool eq_routine_name(const LEX_CSTRING &name1,
                               const LEX_CSTRING &name2)
   {
@@ -153,6 +163,7 @@ public:
     return m_empty_body;
   }
   virtual MDL_key::enum_mdl_namespace get_mdl_type() const= 0;
+  virtual const Sp_handler *sp_handler_mysql_proc() const { return this; }
   virtual sp_cache **get_cache(THD *) const { return NULL; }
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
   virtual HASH *get_priv_hash() const { return NULL; }
@@ -434,6 +445,7 @@ public:
     DBUG_ASSERT(0);
     return MDL_key::TRIGGER;
   }
+  const Sp_handler *sp_handler_mysql_proc() const { return NULL; }
 };