Bug #25382: Passing NULL to an UDF called from stored procedures

 crashes server
 Check for null value is reliable only after calling some of the 
 val_xxx() methods. If the val_xxx() method is not called
 the null_value flag will be set only for certain types of NULL
 values (like SQL constant NULLs for example).
 This caused a crash while trying to dereference a NULL pointer
 that is returned by val_str() for NULL values.
 Fixed by swapping the order of val_xxx() and null_value check.


mysql-test/r/udf.result:
  Bug #25382: Passing NULL to an UDF called from stored procedures 
   crashes server
   - test case
mysql-test/t/udf.test:
  Bug #25382: Passing NULL to an UDF called from stored procedures 
   crashes server
   - test case
sql/item_func.cc:
  Bug #25382: Passing NULL to an UDF called from stored procedures 
   crashes server
   - reliably check null_value

1 files changed, 34 insertions, 0 deletions

diff --git a/mysql-test/r/udf.result b/mysql-test/r/udf.result
index 64b7111bbc8..d5f59247084 100644
--- a/mysql-test/r/udf.result
+++ b/mysql-test/r/udf.result
@@ -240,3 +240,37 @@ drop table bug18761;
 select is_const((1,2,3));
 ERROR 21000: Operand should contain 1 column(s)
 drop function if exists is_const;
+CREATE FUNCTION metaphon RETURNS STRING SONAME "UDF_EXAMPLE_LIB";
+CREATE FUNCTION myfunc_double RETURNS REAL SONAME "UDF_EXAMPLE_LIB";
+CREATE FUNCTION myfunc_int RETURNS INTEGER SONAME "UDF_EXAMPLE_LIB";
+create function f1(p1 varchar(255))
+returns varchar(255)
+begin
+return metaphon(p1);
+end//
+create function f2(p1 varchar(255))
+returns double
+begin
+return myfunc_double(p1);
+end//
+create function f3(p1 varchar(255))
+returns double
+begin
+return myfunc_int(p1);
+end//
+select f3(NULL);
+f3(NULL)
+0
+select f2(NULL);
+f2(NULL)
+NULL
+select f1(NULL);
+f1(NULL)
+NULL
+drop function f1;
+drop function f2;
+drop function f3;
+drop function metaphon;
+drop function myfunc_double;
+drop function myfunc_int;
+End of 5.0 tests.