bug #21888 (Query on GEOMETRY field crashes the server)

RTree keys are really different from BTree and need specific
paramters to be set by optimizer to work.
Sometimes optimizer doesn't set those properly.
Here we decided just to add code to check that the parameters
are correct. Hope to fix optimizer sometimes.

myisam/mi_range.c

@@ -71,6 +71,21 @@ ha_rows mi_records_in_range(MI_INFO *info, int inx, key_range *min_key,
     uchar * key_buff;
     uint start_key_len;
 
+    /*
+      The problem is that the optimizer doesn't support
+      RTree keys properly at the moment.
+      Hope this will be fixed some day.
+      But now NULL in the min_key means that we
+      didn't make the task for the RTree key
+      and expect BTree functionality from it.
+      As it's not able to handle such request
+      we return the error.
+    */
+    if (!min_key)
+    {
+      res= HA_POS_ERROR;
+      break;
+    }
     key_buff= info->lastkey+info->s->base.max_key_length;
     start_key_len= _mi_pack_key(info,inx, key_buff,
                                 (uchar*) min_key->key, min_key->length,

mysql-test/r/gis-rtree.result

@@ -857,3 +857,14 @@ CHECK TABLE t1 EXTENDED;
 Table	Op	Msg_type	Msg_text
 test.t1	check	status	OK
 DROP TABLE t1;
+CREATE TABLE t1 (foo GEOMETRY NOT NULL, SPATIAL INDEX(foo) );
+INSERT INTO t1 (foo) VALUES (PointFromWKB(POINT(1,1)));
+INSERT INTO t1 (foo) VALUES (PointFromWKB(POINT(1,0)));
+INSERT INTO t1 (foo) VALUES (PointFromWKB(POINT(0,1)));
+INSERT INTO t1 (foo) VALUES (PointFromWKB(POINT(0,0)));
+SELECT 1 FROM t1 WHERE foo != PointFromWKB(POINT(0,0));
+1
+1
+1
+1
+DROP TABLE t1;

mysql-test/t/gis-rtree.test

@@ -232,4 +232,14 @@ INSERT INTO t1 (c1) VALUES (
 CHECK TABLE t1 EXTENDED;
 DROP TABLE t1;
 
+#
+# Bug #21888: Query on GEOMETRY field using PointFromWKB() results in lost connection
+#
+CREATE TABLE t1 (foo GEOMETRY NOT NULL, SPATIAL INDEX(foo) );
+INSERT INTO t1 (foo) VALUES (PointFromWKB(POINT(1,1)));
+INSERT INTO t1 (foo) VALUES (PointFromWKB(POINT(1,0)));
+INSERT INTO t1 (foo) VALUES (PointFromWKB(POINT(0,1)));
+INSERT INTO t1 (foo) VALUES (PointFromWKB(POINT(0,0)));
+SELECT 1 FROM t1 WHERE foo != PointFromWKB(POINT(0,0));
+DROP TABLE t1;
 # End of 4.1 tests