From 0e00079ff0a13a36ab19ec5611a1112ab9d739df Mon Sep 17 00:00:00 2001
From: Even Rouault <even.rouault@spatialys.com>
Date: Thu, 1 Feb 2024 13:13:44 +0100
Subject: [PATCH 1/2] OGRGeometryFactory::createGeometry(): do not assert on
 wkbUnkown input

---
 autotest/cpp/test_ogr.cpp  | 5 +++++
 ogr/ogrgeometryfactory.cpp | 3 +++
 2 files changed, 8 insertions(+)

diff --git a/autotest/cpp/test_ogr.cpp b/autotest/cpp/test_ogr.cpp
index 448b40b41aa6..0d3044633a28 100644
--- a/autotest/cpp/test_ogr.cpp
+++ b/autotest/cpp/test_ogr.cpp
@@ -425,6 +425,11 @@ TEST_F(test_ogr, geometry_get_point)
     }
 }
 
+TEST_F(test_ogr, OGR_G_CreateGeometry_unknown)
+{
+    EXPECT_EQ(OGR_G_CreateGeometry(wkbUnknown), nullptr);
+}
+
 TEST_F(test_ogr, style_manager)
 {
     OGRStyleMgrH hSM = OGR_SM_Create(nullptr);
diff --git a/ogr/ogrgeometryfactory.cpp b/ogr/ogrgeometryfactory.cpp
index 0cf4395f98fa..8e54c8c9ca46 100644
--- a/ogr/ogrgeometryfactory.cpp
+++ b/ogr/ogrgeometryfactory.cpp
@@ -621,6 +621,9 @@ OGRGeometryFactory::createGeometry(OGRwkbGeometryType eGeometryType)
             poGeom = new (std::nothrow) OGRTriangulatedSurface();
             break;
 
+        case wkbUnknown:
+            break;
+
         default:
             CPLAssert(false);
             break;

From 73d4ccb5f06b7299ca39119b1b6b47380e0a80a4 Mon Sep 17 00:00:00 2001
From: Even Rouault <even.rouault@spatialys.com>
Date: Thu, 1 Feb 2024 13:05:45 +0100
Subject: [PATCH 2/2] OGRGeometryFactory::forceTo(): fix assertion with empty
 geometry and target type = unknown

Found by CIFuzz: https://github.com/OSGeo/gdal/actions/runs/7740101693/job/21105197876?pr=9166
---
 autotest/ogr/ogr_factory.py | 25 +++++++++++++++++++++++++
 ogr/ogrgeometryfactory.cpp  |  8 ++++----
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/autotest/ogr/ogr_factory.py b/autotest/ogr/ogr_factory.py
index 14a084a9de73..d1a7c1a8cf6e 100755
--- a/autotest/ogr/ogr_factory.py
+++ b/autotest/ogr/ogr_factory.py
@@ -902,6 +902,31 @@ def test_ogr_factory_8():
         ogrtest.check_feature_geometry(dst_geom, exp_wkt)
 
 
+###############################################################################
+# Test forceTo() to wkbUnknown
+
+
+@pytest.mark.parametrize(
+    "src_wkt,target_type,exp_wkt",
+    [
+        (
+            "POINT (1 2)",
+            ogr.wkbUnknown,
+            "POINT (1 2)",
+        ),
+        (
+            "POINT EMPTY",
+            ogr.wkbUnknown,
+            "POINT EMPTY",
+        ),
+    ],
+)
+def test_ogr_factory_forceTo_unknown(src_wkt, target_type, exp_wkt):
+    src_geom = ogr.CreateGeometryFromWkt(src_wkt)
+    dst_geom = ogr.ForceTo(src_geom, target_type)
+    ogrtest.check_feature_geometry(dst_geom, exp_wkt)
+
+
 ###############################################################################
 # Test forceTo()
 
diff --git a/ogr/ogrgeometryfactory.cpp b/ogr/ogrgeometryfactory.cpp
index 8e54c8c9ca46..44647d2915c7 100644
--- a/ogr/ogrgeometryfactory.cpp
+++ b/ogr/ogrgeometryfactory.cpp
@@ -4554,6 +4554,10 @@ OGRGeometry *OGRGeometryFactory::forceTo(OGRGeometry *poGeom,
     if (poGeom == nullptr)
         return poGeom;
 
+    const OGRwkbGeometryType eTargetTypeFlat = wkbFlatten(eTargetType);
+    if (eTargetTypeFlat == wkbUnknown)
+        return poGeom;
+
     if (poGeom->IsEmpty())
     {
         OGRGeometry *poRet = createGeometry(eTargetType);
@@ -4567,10 +4571,6 @@ OGRGeometry *OGRGeometryFactory::forceTo(OGRGeometry *poGeom,
         return poRet;
     }
 
-    const OGRwkbGeometryType eTargetTypeFlat = wkbFlatten(eTargetType);
-    if (eTargetTypeFlat == wkbUnknown)
-        return poGeom;
-
     OGRwkbGeometryType eType = poGeom->getGeometryType();
     OGRwkbGeometryType eTypeFlat = wkbFlatten(eType);