Bug#23303391: HANDLE_FATAL_SIGNAL (SIG=11) IN ALLOC_QUERY

              USING CHARACTER-SET-SERVER=UTF16

This is a backport of Bug#15985752 to mysql-5.5

sql/mysqld.cc

@@ -3482,9 +3482,24 @@ static int init_common_variables()
   /* Set collactions that depends on the default collation */
   global_system_variables.collation_server=	 default_charset_info;
   global_system_variables.collation_database=	 default_charset_info;
+
+  if (is_supported_parser_charset(default_charset_info))
+  {
     global_system_variables.collation_connection= default_charset_info;
     global_system_variables.character_set_results= default_charset_info;
     global_system_variables.character_set_client= default_charset_info;
+  }
+  else
+  {
+    sql_print_information("'%s' can not be used as client character set. "
+                          "'%s' will be used as default client character set.",
+                          default_charset_info->csname,
+                          my_charset_latin1.csname);
+    global_system_variables.collation_connection= &my_charset_latin1;
+    global_system_variables.character_set_results= &my_charset_latin1;
+    global_system_variables.character_set_client= &my_charset_latin1;
+  }
+
   if (!(character_set_filesystem= 
         get_charset_by_csname(character_set_filesystem_name,
                               MY_CS_PRIMARY, MYF(MY_WME))))

sql/sql_acl.cc

@@ -8789,7 +8789,10 @@ static ulong parse_client_handshake_packet(MPVIO_EXT *mpvio,
   {
     mpvio->client_capabilities= uint4korr(end);
     mpvio->max_client_packet_length= 0xfffff;
-    charset_code= default_charset_info->number;
+    charset_code= global_system_variables.character_set_client->number;
+    sql_print_warning("Client failed to provide its character set. "
+                      "'%s' will be used as client character set.",
+                      global_system_variables.character_set_client->csname);
     if (mpvio->charset_adapter->init_client_charset(charset_code))
       return packet_error;
     goto skip_to_ssl;
@@ -8826,7 +8829,10 @@ static ulong parse_client_handshake_packet(MPVIO_EXT *mpvio,
       Old clients didn't have their own charset. Instead the assumption
       was that they used what ever the server used.
     */
-    charset_code= default_charset_info->number;
+    charset_code= global_system_variables.character_set_client->number;
+    sql_print_warning("Client failed to provide its character set. "
+                      "'%s' will be used as client character set.",
+                      global_system_variables.character_set_client->csname);
   }
   DBUG_EXECUTE_IF("host_error_charset",
                   {

sql/sql_connect.cc

 /*
-   Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2007, 2016, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -431,6 +431,14 @@ bool thd_init_client_charset(THD *thd, uint cs_number)
                      global_system_variables.character_set_client->name,
                      cs->name))
   {
+    if (!is_supported_parser_charset(
+         global_system_variables.character_set_client))
+    {
+      /* Disallow non-supported parser character sets: UCS2, UTF16, UTF32 */
+      my_error(ER_WRONG_VALUE_FOR_VAR, MYF(0), "character_set_client",
+               global_system_variables.character_set_client->csname);
+      return true;
+    }
     thd->variables.character_set_client=
       global_system_variables.character_set_client;
     thd->variables.collation_connection=