Fix potential crashes in geometry checker (identified by Coverity)

nyalldawson · nyalldawson · commit a9370af19c2f · 2017-05-29T09:29:53.000+10:00
diff --git a/src/plugins/geometry_checker/checks/qgsgeometryanglecheck.cpp b/src/plugins/geometry_checker/checks/qgsgeometryanglecheck.cpp
@@ -89,6 +89,11 @@ void QgsGeometryAngleCheck::fixError( QgsGeometryCheckError *error, int method,
 
   // Check if error still applies
   int n = QgsGeometryCheckerUtils::polyLineSize( geometry, vidx.part, vidx.ring );
+  if ( n == 0 )
+  {
+    error->setObsolete();
+    return;
+  }
   const QgsPointV2 &p1 = geometry->vertexAt( QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex - 1 + n ) % n ) );
   const QgsPointV2 &p2 = geometry->vertexAt( vidx );
   const QgsPointV2 &p3 = geometry->vertexAt( QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex + 1 ) % n ) );
diff --git a/src/plugins/geometry_checker/checks/qgsgeometryduplicatenodescheck.cpp b/src/plugins/geometry_checker/checks/qgsgeometryduplicatenodescheck.cpp
@@ -73,6 +73,11 @@ void QgsGeometryDuplicateNodesCheck::fixError( QgsGeometryCheckError *error, int
 
   // Check if error still applies
   int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, vidx.part, vidx.ring );
+  if ( nVerts == 0 )
+  {
+    error->setObsolete();
+    return;
+  }
   QgsPointV2 pi = geom->vertexAt( QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex + nVerts - 1 ) % nVerts ) );
   QgsPointV2 pj = geom->vertexAt( error->vidx() );
   if ( QgsGeometryUtils::sqrDistance2D( pi, pj ) >= QgsGeometryCheckPrecision::tolerance() * QgsGeometryCheckPrecision::tolerance() )
diff --git a/src/plugins/geometry_checker/checks/qgsgeometrysegmentlengthcheck.cpp b/src/plugins/geometry_checker/checks/qgsgeometrysegmentlengthcheck.cpp
@@ -79,6 +79,12 @@ void QgsGeometrySegmentLengthCheck::fixError( QgsGeometryCheckError *error, int
 
   // Check if error still applies
   int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, vidx.part, vidx.ring );
+  if ( nVerts == 0 )
+  {
+    error->setObsolete();
+    return;
+  }
+
   QgsPointV2 pi = geom->vertexAt( error->vidx() );
   QgsPointV2 pj = geom->vertexAt( QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex - 1 + nVerts ) % nVerts ) );
   double dist = qSqrt( QgsGeometryUtils::sqrDistance2D( pi, pj ) );
diff --git a/src/plugins/geometry_checker/checks/qgsgeometryselfintersectioncheck.cpp b/src/plugins/geometry_checker/checks/qgsgeometryselfintersectioncheck.cpp
@@ -110,7 +110,7 @@ void QgsGeometrySelfIntersectionCheck::fixError( QgsGeometryCheckError *error, i
   // Check if error still applies
   bool ringIsClosed = false;
   int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, vidx.part, vidx.ring, &ringIsClosed );
-  if ( inter.segment1 >= nVerts || inter.segment2 >= nVerts )
+  if ( nVerts == 0 || inter.segment1 >= nVerts || inter.segment2 >= nVerts )
   {
     error->setObsolete();
     return;

Original file line number	Diff line number	Diff line change
`@@ -110,7 +110,7 @@ void QgsGeometrySelfIntersectionCheck::fixError( QgsGeometryCheckError *error, i`
`110`	`110`	`// Check if error still applies`
`111`	`111`	`bool ringIsClosed = false;`
`112`	`112`	`int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, vidx.part, vidx.ring, &ringIsClosed );`
`113`		`- if ( inter.segment1 >= nVerts \|\| inter.segment2 >= nVerts )`
	`113`	`+ if ( nVerts == 0 \|\| inter.segment1 >= nVerts \|\| inter.segment2 >= nVerts )`
`114`	`114`	`{`
`115`	`115`	`error->setObsolete();`
`116`	`116`	`return;`