[geos-devel] [GEOS] #1111: BUG: C API: ownership of passed-in geometry not always transferred prior to exception

[GEOS]

#1111: BUG: C API: ownership of passed-in geometry not always transferred prior to
exception
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 Reporter:  Brendan Ward  |      Owner:  geos-devel@…
     Type:  defect        |     Status:  new
 Priority:  major         |  Milestone:  3.10.0
Component:  Default       |    Version:  3.9.0
 Severity:  Unassigned    |   Keywords:
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 In general, the create* functions that take other geometries as inputs
 (e.g., GEOSGeom_createPolygon_r) and take ownership of the passed-in
 geometries on success are supposed to clean them up on failure.

 However, in exception cases (which return NULL for the geometry to be
 created), this isn't handled consistently, which can lead to memory leaks
 because the caller assumes that those geometries are automatically cleaned
 up on failure.  For the cases where the ownership is transferred
 immediately, the caller will segfault if it tries to clean them up.

 If the geometry inputs need to be validated before ultimately using them
 to construct the returned geometry, those should be destroyed before
 returning NULL.

 I haven't done a full review of these create* functions, but
 GEOSGeom_createPolygon_r looks problematic.

 It looks like ownership is transferred early for
 GEOSGeom_createLinearRing_r and GEOSGeom_createLineString_r, so those are
 probably OK.

 (this was discussed a bit on IRC)

-- 
Ticket URL: <https://trac.osgeo.org/geos/ticket/1111>
GEOS <http://trac.osgeo.org/geos>
GEOS (Geometry Engine - Open Source) is a C++ port of the Java Topology Suite (JTS).