Bug#11765139 58069: LOAD DATA INFILE: VALGRIND REPORTS INVALID MEMORY READS AND WRITES WITH U

Some multibyte sequences could be considered by my_mbcharlen() functions
as multibyte character but more exact my_ismbchar() does not think so.
In such a case this multibyte sequences is pushed into 'stack' buffer which
is too small to accommodate the sequence.
The fix is to allocate stack buffer in
compliance with max character length.

mysql-test/r/loaddata.result

@@ -532,4 +532,11 @@ a
 0
 1
 DROP TABLE t1;
+#
+# Bug#11765139  58069: LOAD DATA INFILE: VALGRIND REPORTS INVALID MEMORY READS AND WRITES WITH U
+#
+CREATE TABLE t1(f1 INT);
+SELECT 0xE1BB30 INTO OUTFILE 't1.dat';
+LOAD DATA INFILE 't1.dat' IGNORE INTO TABLE t1 CHARACTER SET utf8;
+DROP TABLE t1;
 End of 5.1 tests

mysql-test/t/loaddata.test

@@ -611,5 +611,18 @@ DROP TABLE t1;
 let $MYSQLD_DATADIR= `select @@datadir`;
 remove_file $MYSQLD_DATADIR/test/tmpp2.txt;
 
+--echo #
+--echo # Bug#11765139  58069: LOAD DATA INFILE: VALGRIND REPORTS INVALID MEMORY READS AND WRITES WITH U
+--echo #
+
+CREATE TABLE t1(f1 INT);
+EVAL SELECT 0xE1BB30 INTO OUTFILE 't1.dat';
+--disable_warnings
+LOAD DATA INFILE 't1.dat' IGNORE INTO TABLE t1 CHARACTER SET utf8;
+--enable_warnings
+
+DROP TABLE t1;
+let $MYSQLD_DATADIR= `select @@datadir`;
+remove_file $MYSQLD_DATADIR/test/t1.dat;
 
 --echo End of 5.1 tests

sql/sql_load.cc

@@ -1109,7 +1109,7 @@ READ_INFO::READ_INFO(File file_par, uint tot_length, CHARSET_INFO *cs,
 
 
   /* Set of a stack for unget if long terminators */
-  uint length=max(field_term_length,line_term_length)+1;
+  uint length= max(cs->mbmaxlen, max(field_term_length, line_term_length)) + 1;
   set_if_bigger(length,line_start.length());
   stack=stack_pos=(int*) sql_alloc(sizeof(int)*length);