Bug#44358 valgrind errors with decode() function

The warning happens because string argument is not zero ended.
The fix is to add new parameter 'length' to SQL_CRYPT() and
use ptr() instead of c_ptr().

mysql-test/r/func_str.result

@@ -2526,3 +2526,17 @@ h	i
 31.12.2008	AAAAAA, aaaaaa
 DROP TABLE t1;
 End of 5.0 tests
+drop table if exists t1;
+create table t1(f1 tinyint default null)engine=myisam;
+insert into t1 values (-1),(null);
+explain select 1 as a from t1,(select decode(f1,f1) as b from t1) a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	PRIMARY	<derived2>	ALL	NULL	NULL	NULL	NULL	2	Using join buffer
+2	DERIVED	t1	ALL	NULL	NULL	NULL	NULL	2	
+explain select 1 as a from t1,(select encode(f1,f1) as b from t1) a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	PRIMARY	<derived2>	ALL	NULL	NULL	NULL	NULL	2	Using join buffer
+2	DERIVED	t1	ALL	NULL	NULL	NULL	NULL	2	
+drop table t1;

mysql-test/t/func_str.test

@@ -1283,3 +1283,15 @@ SELECT DATE_FORMAT(c, GET_FORMAT(DATE, 'eur')) h, CONCAT(UPPER(aa),', ', aa) i F
 DROP TABLE t1;
 
 --echo End of 5.0 tests
+
+#
+# Bug#44358 valgrind errors with decode() function
+#
+--disable_warnings
+drop table if exists t1;
+--enable_warnings
+create table t1(f1 tinyint default null)engine=myisam;
+insert into t1 values (-1),(null);
+explain select 1 as a from t1,(select decode(f1,f1) as b from t1) a;
+explain select 1 as a from t1,(select encode(f1,f1) as b from t1) a;
+drop table t1;

sql/item_strfunc.cc

@@ -1742,7 +1742,7 @@ String *Item_func_encode::val_str(String *str)
 
   null_value=0;
   res=copy_if_not_alloced(str,res,res->length());
-  SQL_CRYPT sql_crypt(password->ptr());
+  SQL_CRYPT sql_crypt(password->ptr(), password->length());
   sql_crypt.init();
   sql_crypt.encode((char*) res->ptr(),res->length());
   res->set_charset(&my_charset_bin);
@@ -1771,7 +1771,7 @@ String *Item_func_decode::val_str(String *str)
 
   null_value=0;
   res=copy_if_not_alloced(str,res,res->length());
-  SQL_CRYPT sql_crypt(password->ptr());
+  SQL_CRYPT sql_crypt(password->ptr(), password->length());
   sql_crypt.init();
   sql_crypt.decode((char*) res->ptr(),res->length());
   return res;

sql/sql_crypt.cc

@@ -28,10 +28,10 @@
 
 #include "mysql_priv.h"
 
-SQL_CRYPT::SQL_CRYPT(const char *password)
+SQL_CRYPT::SQL_CRYPT(const char *password, uint length)
 {
   ulong rand_nr[2];
-  hash_password(rand_nr,password, (uint) strlen(password));
+  hash_password(rand_nr,password, length);
   crypt_init(rand_nr);
 }
 

sql/sql_crypt.h

@@ -25,7 +25,7 @@ class SQL_CRYPT :public Sql_alloc
   uint shift;
   void crypt_init(ulong *seed);
  public:
-  SQL_CRYPT(const char *seed);
+  SQL_CRYPT(const char *seed, uint length);
   SQL_CRYPT(ulong *seed)
   {
     crypt_init(seed);