Fixed memory overrun in binlog_encryption.encrypted_master

Problem was that max_row_lengt() used different bitmap
than pack_row()

sql/sql_class.cc

@@ -6414,7 +6414,8 @@ int THD::binlog_write_row(TABLE* table, bool is_trans,
     Pack records into format for transfer. We are allocating more
     memory than needed, but that doesn't matter.
   */
-  Row_data_memory memory(table, max_row_length(table, record));
+  Row_data_memory memory(table, max_row_length(table, table->rpl_write_set,
+                                               record));
   if (!memory.has_memory())
     return HA_ERR_OUT_OF_MEM;
 
@@ -6451,8 +6452,10 @@ int THD::binlog_update_row(TABLE* table, bool is_trans,
   DBUG_ASSERT(is_current_stmt_binlog_format_row() &&
             ((WSREP(this) && wsrep_emulate_bin_log) || mysql_bin_log.is_open()));
 
-  size_t const before_maxlen = max_row_length(table, before_record);
-  size_t const after_maxlen  = max_row_length(table, after_record);
+  size_t const before_maxlen= max_row_length(table, table->read_set,
+                                             before_record);
+  size_t const after_maxlen=  max_row_length(table, table->rpl_write_set,
+                                             after_record);
 
   Row_data_memory row_data(table, before_maxlen, after_maxlen);
   if (!row_data.has_memory())
@@ -6528,7 +6531,8 @@ int THD::binlog_delete_row(TABLE* table, bool is_trans,
      Pack records into format for transfer. We are allocating more
      memory than needed, but that doesn't matter.
   */
-  Row_data_memory memory(table, max_row_length(table, record));
+  Row_data_memory memory(table, max_row_length(table, table->read_set,
+                                               record));
   if (unlikely(!memory.has_memory()))
     return HA_ERR_OUT_OF_MEM;
 

sql/table.cc

@@ -7279,7 +7279,7 @@ bool TABLE_LIST::process_index_hints(TABLE *tbl)
 }
 
 
-size_t max_row_length(TABLE *table, const uchar *data)
+size_t max_row_length(TABLE *table, MY_BITMAP const *cols, const uchar *data)
 {
   TABLE_SHARE *table_s= table->s;
   size_t length= table_s->reclength + 2 * table_s->fields;
@@ -7291,11 +7291,11 @@ size_t max_row_length(TABLE *table, const uchar *data)
   for (uint *ptr= beg ; ptr != end ; ++ptr)
   {
     Field * const field= table->field[*ptr];
-    if (bitmap_is_set(table->read_set, field->field_index) &&
+    if (bitmap_is_set(cols, field->field_index) &&
         !field->is_null(rec_offset))
     {
       Field_blob * const blob= (Field_blob*) field;
-      length+= blob->get_length(rec_offset) + HA_KEY_BLOB_LENGTH;
+      length+= blob->get_length(rec_offset) + 8; /* max blob store length */
     }
   }
   DBUG_PRINT("exit", ("length: %lld", (longlong) length));

sql/table.h

@@ -2672,7 +2672,7 @@ enum get_table_share_flags {
   GTS_FORCE_DISCOVERY      = 16
 };
 
-size_t max_row_length(TABLE *table, const uchar *data);
+size_t max_row_length(TABLE *table, MY_BITMAP const *cols, const uchar *data);
 
 void init_mdl_requests(TABLE_LIST *table_list);