Bug#54041: MySQL 5.0.92 fails when tests from Connector/C suite run

The problem was that a user could supply supply data in chunks
via the COM_STMT_SEND_LONG_DATA command to prepared statement
parameter other than of type TEXT or BLOB. This posed a problem
since other parameter types aren't setup to handle long data,
which would lead to a crash when attempting to use the supplied
data.

Given that long data can be supplied at any stage of a prepared
statement, coupled with the fact that the type of a parameter
marker might change between consecutive executions, the solution
is to validate at execution time each parameter marker for which
a data stream was provided. If the parameter type is not TEXT or
BLOB (that is, if the type is not able to handle a data stream),
a error is returned.

sql/sql_prepare.cc

@@ -674,6 +674,18 @@ static void setup_one_conversion_function(THD *thd, Item_param *param,
 }
 
 #ifndef EMBEDDED_LIBRARY
+
+/**
+  Check whether this parameter data type is compatible with long data.
+  Used to detect whether a long data stream has been supplied to a
+  incompatible data type.
+*/
+inline bool is_param_long_data_type(Item_param *param)
+{
+  return ((param->param_type >= MYSQL_TYPE_TINY_BLOB) &&
+          (param->param_type <= MYSQL_TYPE_STRING));
+}
+
 /*
   Routines to assign parameters from data supplied by the client.
 
@@ -737,6 +749,14 @@ static bool insert_params_withlog(Prepared_statement *stmt, uchar *null_array,
           DBUG_RETURN(1);
       }
     }
+    /*
+      A long data stream was supplied for this parameter marker.
+      This was done after prepare, prior to providing a placeholder
+      type (the types are supplied at execute). Check that the
+      supplied type of placeholder can accept a data stream.
+    */
+    else if (!is_param_long_data_type(param))
+      DBUG_RETURN(1);
     res= param->query_val_str(&str);
     if (param->convert_str_value(thd))
       DBUG_RETURN(1);                           /* out of memory */
@@ -775,6 +795,14 @@ static bool insert_params(Prepared_statement *stmt, uchar *null_array,
           DBUG_RETURN(1);
       }
     }
+    /*
+      A long data stream was supplied for this parameter marker.
+      This was done after prepare, prior to providing a placeholder
+      type (the types are supplied at execute). Check that the
+      supplied type of placeholder can accept a data stream.
+    */
+    else if (is_param_long_data_type(param))
+      DBUG_RETURN(1);
     if (param->convert_str_value(stmt->thd))
       DBUG_RETURN(1);                           /* out of memory */
   }

tests/mysql_client_test.c

@@ -16757,6 +16757,63 @@ static void test_bug53907()
 }
 
 
+/**
+  Bug#54041: MySQL 5.0.92 fails when tests from Connector/C suite run
+*/
+
+static void test_bug54041()
+{
+  int rc;
+  MYSQL_STMT *stmt;
+  MYSQL_BIND bind;
+
+  DBUG_ENTER("test_bug54041");
+  myheader("test_bug54041");
+
+  rc= mysql_query(mysql, "DROP TABLE IF EXISTS t1");
+  myquery(rc);
+
+  rc= mysql_query(mysql, "CREATE TABLE t1 (a INT)");
+  myquery(rc);
+
+  stmt= mysql_simple_prepare(mysql, "INSERT INTO t1 (a) VALUES (?)");
+  check_stmt(stmt);
+  verify_param_count(stmt, 1);
+
+  memset(&bind, 0, sizeof(bind));
+
+  /* Any type that does not support long data handling. */
+  bind.buffer_type= MYSQL_TYPE_LONG;
+
+  rc= mysql_stmt_bind_param(stmt, &bind);
+  check_execute(stmt, rc);
+
+  /*
+    Trick the client API into sending a long data packet for
+    the parameter. Long data is only supported for string and
+    binary types.
+  */
+  stmt->params[0].buffer_type= MYSQL_TYPE_STRING;
+
+  rc= mysql_stmt_send_long_data(stmt, 0, "data", 5);
+  check_execute(stmt, rc);
+
+  /* Undo API violation. */
+  stmt->params[0].buffer_type= MYSQL_TYPE_LONG;
+
+  rc= mysql_stmt_execute(stmt);
+  /* Incorrect arguments. */
+  check_execute_r(stmt, rc);
+
+  mysql_stmt_close(stmt);
+
+  rc= mysql_query(mysql, "DROP TABLE IF EXISTS t1");
+  myquery(rc);
+
+  DBUG_VOID_RETURN;
+}
+
+
 /*
   Read and parse arguments and MySQL options from my.cnf
 */
@@ -17062,6 +17119,7 @@ static struct my_tests_st my_tests[]= {
   { "test_bug45010", test_bug45010 },
   { "test_bug53371", test_bug53371 },
   { "test_bug53907", test_bug53907 },
+  { "test_bug54041", test_bug54041 },
   { 0, 0 }
 };