Bug#31705 Partitions: crash if varchar length > 65530

Buffer overflow due to wrong key length in partitioning

Changed to the correct key_length function.


sql/opt_range.cc:
  Bug#31705 Partitions: crash if varchar length > 65530
  Problem: buffer overflow due to wrong key-length
  
  Fix: Using correct key_length function
mysql-test/r/partition_datatype.result:
  Bug#31705 Partitions: crash if varchar length > 65530
  New test-result case for testing all column types
  used in key-partitioning.
  
  (For verifying correct key-length use)
mysql-test/t/partition_datatype.test:
  Bug#31705 Partitions: crash if varchar length > 65530 
  New test case for testing all column types
  used in key-partitioning.
  
  (For verifying correct key-length used)

1 files changed, 4 insertions, 6 deletions

diff --git a/sql/opt_range.cc b/sql/opt_range.cc
index 99c28be36b0..b89e8b3dcbb 100644
--- a/sql/opt_range.cc
+++ b/sql/opt_range.cc
@@ -3344,18 +3344,16 @@ static bool create_partition_index_description(PART_PRUNE_PARAM *ppar)
   {
     key_part->key=          0;
     key_part->part=	    part;
-    key_part->length=       (uint16) (*field)->pack_length_in_rec();
-    /* 
-      psergey-todo: check yet again if this is correct for tricky field types,
-      e.g. see "Fix a fatal error in decimal key handling" in open_binary_frm()
-    */
-    key_part->store_length= (uint16) (*field)->pack_length();
+    key_part->store_length= key_part->length= (uint16) (*field)->key_length();
     if ((*field)->real_maybe_null())
       key_part->store_length+= HA_KEY_NULL_LENGTH;
     if ((*field)->type() == MYSQL_TYPE_BLOB || 
         (*field)->real_type() == MYSQL_TYPE_VARCHAR)
       key_part->store_length+= HA_KEY_BLOB_LENGTH;
 
+    DBUG_PRINT("info", ("part %u length %u store_length %u", part,
+                         key_part->length, key_part->store_length));
+
     key_part->field=        (*field);
     key_part->image_type =  Field::itRAW;
     /*