Bug #74371 Valgrind: Memory leak when doing spatial operations on geometrycollections
Submitted: 14 Oct 2014 11:32 Modified: 31 Oct 2014 15:18
Reporter: Norvald Ryeng Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: GIS Severity:S3 (Non-critical)
Version:5.7.6 OS:Any
Assigned to: CPU Architecture:Any

[14 Oct 2014 11:32] Norvald Ryeng
Description:
2,592 bytes in 16 blocks are definitely lost in loss record 47 of 49
   at 0x4C2AB80: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0xF40E5B: my_raw_malloc (my_malloc.c:171)
   by 0xF40AE9: my_malloc (my_malloc.c:51)
   by 0xD67713: String::mem_realloc(unsigned long) (sql_string.cc:102)
   by 0x9779CD: String::reserve(unsigned long) (sql_string.h:475)
   by 0x9E9D3B: BG_geometry_collection::store(Geometry const*) (item_geofunc.cc:3073)
   by 0x9E9C75: BG_geometry_collection::store_geometry(Geometry const*) (item_geofunc.cc:3051)
   by 0x9F69A6: BG_geometry_collection::fill(Geometry const*) (item_geofunc.h:119)
   by 0xA0B417: Geometry* Item_func_spatial_operation::geocol_intersection<double, boost::geometry::cs::cartesian>(Geometry*, Geometry*, String*, bool*) (item_geofunc.cc:7475)
   by 0xA008C0: Geometry* Item_func_spatial_operation::geometry_collection_set_operation<double, boost::geometry::cs::cartesian>(Geometry*, Geometry*, String*, bool*) (item_geofunc.cc:7401)
   by 0x9EB8CF: Item_func_spatial_operation::val_str(String*) (item_geofunc.cc:7214)
   by 0x9E5E42: Item_func_as_wkt::val_str_ascii(String*) (item_geofunc.cc:1386)
   by 0xB30EEB: Item_str_func::val_str_from_val_str_ascii(String*, String*) (item_strfunc.cc:82)
   by 0x9B450F: Item_str_ascii_func::val_str(String*) (item_strfunc.h:114)
   by 0x96E581: Item::send(Protocol*, String*) (item.cc:6941)
   by 0xB9ED87: Protocol::send_result_set_row(List<Item>*) (protocol.cc:1005)

How to repeat:
SET @a=ST_GeomFromText('GEOMETRYCOLLECTION(MULTIPOLYGON('
  '((0 0,1 0,1 1,0 1,0 0)),((1 1,10 1,10 10,1 10,1 1),'
  '(4 4,6 4,6 6,4 6,4 4))))');

SET @b=GeometryCollection(
Point(1,1),
LineString(Point(1,1),Point(2,2)),
Polygon(LineString(Point(0,0),Point(1,0),Point(1,1),
  Point(0,1),Point(0,0))),
Polygon(LineString(Point(0,0),Point(10,0),Point(10,10),
  Point(0,10),Point(0,0)),LineString(Point(4,4),Point(6,4),
  Point(6,6),Point(4,6),Point(4,4))),
MultiPoint(Point(1,1),Point(2,2)),
MultiLineString(Linestring(Point(1,1),Point(2,2)),
  LineString(Point(3,3),Point(4,4))),
MultiPolygon(Polygon(Linestring(Point(0,0),Point(1,0),
  Point(1,1),Point(0,1),Point(0,0))),
  Polygon(Linestring(Point(5,5),Point(10,5),Point(10,10),
  Point(5,10),Point(5,5)))),
MultiPolygon(Polygon(LineString(Point(0,0),Point(1,0),
  Point(1,1),Point(0,1),Point(0,0))),
  Polygon(Linestring(Point(5,5),Point(10,5),Point(10,10),
  Point(5,10),Point(5,5)),Linestring(Point(6,6),Point(7,6),
  Point(7,7),Point(6,7),Point(6,6)))),
GeometryCollection(Point(1,1)),
GeometryCollection(LineString(Point(1,1),Point(2,2))),
GeometryCollection(Polygon(LineString(Point(0,0),Point(1,0),
  Point(1,1),Point(0,1),Point(0,0)))),
GeometryCollection(Polygon(Linestring(Point(0,0),
  Point(10,0),Point(10,10),Point(0,10),Point(0,0)),
  Linestring(Point(4,4),Point(6,4),Point(6,6),Point(4,6),
  Point(4,4)))),
GeometryCollection(MultiPoint(Point(1,1),Point(2,2))),
GeometryCollection(MultiLineString(Linestring(Point(1,1),
  Point(2,2)),LineString(Point(3,3),Point(4,4)))),
GeometryCollection(MultiPolygon(Polygon(Linestring(
  Point(0,0),Point(1,0),Point(1,1),Point(0,1),Point(0,0))),
  Polygon(Linestring(Point(5,5),Point(10,5),Point(10,10),
  Point(5,10),Point(5,5))))),
GeometryCollection(MultiPolygon(Polygon(LineString(
  Point(0,0),Point(1,0),Point(1,1),Point(0,1),Point(0,0))),
  Polygon(Linestring(Point(5,5),Point(10,5),Point(10,10),
  Point(5,10),Point(5,5)),Linestring(Point(6,6),Point(7,6),
  Point(7,7),Point(6,7),Point(6,6)))))
);

SELECT AsText(ST_Intersection(@a, @b));

Suggested fix:
Don't leak.
[31 Oct 2014 15:18] Paul Dubois
Noted in 5.7.6 changelogs.

Depending on contents, geometry collection objects were not properly
destroyed, resulting in a memory leak.