Improving checks for unhandled error issues

Author: olivieriluca

go-lisa/go-testcases/unhandled-errors/hf-unhandled-errors.go

@@ -17,6 +17,8 @@ func (t *SimpleAsset) Invoke(stub shim.ChaincodeStubInterface) peer.Response {
 	value1, _ := stub.GetState(args[0]) // KO: error is discarded
 
 	stub.PutState(args[0], []byte("ASD")) // KO: error is discarded
+
+	_ = stub.PutState(args[0], []byte("ASD")) // KO: error is discarded
 
 	value2, err := stub.GetState(args[1]) // KO: error is not handled
 

go-lisa/src/main/java/it/unive/golisa/checker/cosmos/panic/ABCIPanicChecker.java

@@ -147,18 +147,11 @@ private boolean hasExplicitRecovery(GoDefer defer, CheckToolWithAnalysisResults<
 		Expression expr = defer.getSubExpression();
 		if(expr instanceof CFGCall) {
 			CFGCall call = (CFGCall) expr;
-			return call.getTargetedCFGs().stream().anyMatch(cfg -> cfg.getNodes().stream().anyMatch(n -> n instanceof GoRecover || containsRecover(n)));
+			return call.getTargetedCFGs().stream().anyMatch(cfg -> cfg.getNodes().stream().anyMatch(n -> CFGUtils.matchNodeOrSubExpressions(n, st -> st instanceof GoRecover)));
 		}
 		return false;
 	}
 
-
-	private boolean containsRecover(Statement n) {
-		
-		return n instanceof GoRecover;
-	}
-
-
 	private GraphForCheckers extractPathCriticalComponentsInvolvedInPanic(GoPanic node,
 			CheckToolWithAnalysisResults<SimpleAbstractState<PointBasedHeap, ValueEnvironment<DummyDomain>, TypeEnvironment<InferredTypes>>> tool) throws CloneNotSupportedException {
 		GraphForCheckers graph = new GraphForCheckers(node.getLocation().toString());

go-lisa/src/main/java/it/unive/golisa/checker/hf/UnhandledErrorsChecker.java

@@ -1,5 +1,8 @@
 package it.unive.golisa.checker.hf;
 
+import java.util.HashMap;
+import java.util.Map;
+
 import it.unive.golisa.cfg.statement.assignment.GoAssignment;
 import it.unive.golisa.cfg.statement.assignment.GoMultiAssignment;
 import it.unive.golisa.cfg.utils.CFGUtils;
@@ -26,60 +29,99 @@
  */
 public class UnhandledErrorsChecker implements SyntacticCheck {
 
+	private Map<Call, Boolean> assignmentMap;
+	
 	@Override
 	public void beforeExecution(CheckTool tool) {
+		
+		assignmentMap = new HashMap<>();
 	}
 
 	@Override
 	public void afterExecution(CheckTool tool) {
+		
+		for(Call call : assignmentMap.keySet()) {
+			if(!assignmentMap.get(call).booleanValue()) {
+				tool.warnOn(call, "Unhandled error of a blockchain "
+						+ (ReadWriteHFUtils.isReadCall((Call) call) ? "read" : "write")
+						+ " operation. The error seems not assigned in any variable");
+			}
+				
+		}
 	}
 
 	@Override
 	public boolean visit(CheckTool tool, CFG graph, Statement node) {
+		
+		if (node instanceof Call) {
+			if (ReadWriteHFUtils.isReadOrWriteCall((Call) node)) {
+				if(!assignmentMap.containsKey((Call) node))
+					assignmentMap.put((Call) node, Boolean.FALSE);
+			}
+		}
 
 		if (node instanceof GoMultiAssignment) {
 			GoMultiAssignment multiAssign = (GoMultiAssignment) node;
 			Expression expr = multiAssign.getExpressionToAssign();
 			if (expr instanceof Call) {
 				if (ReadWriteHFUtils.isReadOrWriteCall((Call) expr)) {
+					assignmentMap.put((Call) expr, Boolean.TRUE);
 					if (multiAssign.getIds().length == 2)
 						if (multiAssign.getIds()[1] instanceof VariableRef) {
-							VariableRef ref = (VariableRef) multiAssign.getIds()[1];
-							if (GoLangUtils.isBlankIdentifier(ref.getVariable()))
-								tool.warnOn(node,
-										"Unhandled error of a blockchain "
-												+ (ReadWriteHFUtils.isReadCall((Call) expr) ? "read" : "write")
-												+ " operation. It is discarded during the assignment.");
-							else {
-								boolean found = false;
-								for (ControlFlowStructure cfs : graph.getControlFlowStructures()) {
-									if (cfs instanceof IfThenElse) {
-										CodeGraph<CFG, Statement,
-												Edge> path = CFGUtils.getPath(graph, node, cfs.getCondition());
-										if (path != null
-												&& !existVariableOverwriteInPath(path, node, ref)
-												&& isVariableRefUsedInCondition(ref, cfs.getCondition())) {
-											found = true;
-											break;
-										}
-									}
-
-								}
-
-								if (!found)
-									tool.warnOn(node, "Unhandled error of a blockchain "
-											+ (ReadWriteHFUtils.isReadCall((Call) expr) ? "read" : "write")
-											+ " operation. It seems not checked in any condition statements in the method");
-							}
+							checkVariableRef((VariableRef) multiAssign.getIds()[1], (Call) expr, tool, graph, node);
 						}
+				}
 
+			}
+		}
+		
+		if (node instanceof GoAssignment) {
+			GoAssignment assign = (GoAssignment) node;
+			Expression right = assign.getRight();
+			if (right instanceof Call) {
+				if (ReadWriteHFUtils.isWriteCall((Call) right)) {
+					assignmentMap.put((Call) right, Boolean.TRUE);
+					Expression left = assign.getLeft();
+					if (left instanceof VariableRef) {
+						checkVariableRef((VariableRef) left, (Call) right, tool, graph, node);
+					}
 				}
 
 			}
 		}
+		
 		return true;
 	}
 
+	private void checkVariableRef( VariableRef ref, Call call, CheckTool tool, CFG graph, Statement node) {
+		if (GoLangUtils.isBlankIdentifier(ref.getVariable()))
+			tool.warnOn(node,
+					"Unhandled error of a blockchain "
+							+ (ReadWriteHFUtils.isReadCall(call) ? "read" : "write")
+							+ " operation. It is discarded during the assignment.");
+		else {
+			boolean found = false;
+			for (ControlFlowStructure cfs : graph.getControlFlowStructures()) {
+				if (cfs instanceof IfThenElse) {
+					CodeGraph<CFG, Statement,
+							Edge> path = CFGUtils.getPath(graph, node, cfs.getCondition());
+					if (path != null
+							&& !existVariableOverwriteInPath(path, node, ref)
+							&& isVariableRefUsedInCondition(ref, cfs.getCondition())) {
+						found = true;
+						break;
+					}
+				}
+
+			}
+
+			if (!found)
+				tool.warnOn(node, "Unhandled error of a blockchain "
+						+ (ReadWriteHFUtils.isReadCall(call) ? "read" : "write")
+						+ " operation. It seems not checked in any condition statements in the method");
+		}
+	}
+
 	private boolean existVariableOverwriteInPath(CodeGraph<CFG, Statement, Edge> path, Statement node,
 			VariableRef ref) {
 		for (Statement n : path.getNodeList()) {

go-lisa/src/main/java/it/unive/golisa/frontend/GoCodeMemberVisitor.java

@@ -92,6 +92,7 @@
 import it.unive.golisa.cfg.expression.GoMake;
 import it.unive.golisa.cfg.expression.GoNew;
 import it.unive.golisa.cfg.expression.GoPanic;
+import it.unive.golisa.cfg.expression.GoRecover;
 import it.unive.golisa.cfg.expression.GoTypeConversion;
 import it.unive.golisa.cfg.expression.binary.GoBitwiseAnd;
 import it.unive.golisa.cfg.expression.binary.GoBitwiseNAnd;
@@ -2163,6 +2164,9 @@ public Expression visitPrimaryExpr(PrimaryExprContext ctx) {
 				} else {
 					return new GoMake(cfg, locationOf(ctx.primaryExpr()), Untyped.INSTANCE, args);
 				}
+			case "recover":
+				args = visitArguments(ctx.arguments());
+				return new GoRecover(cfg, locationOf(ctx.primaryExpr()));
 			case "panic":
 				args = visitArguments(ctx.arguments());
 				return new GoPanic(cfg, locationOf(ctx.primaryExpr()), args);