Don't ignore override if it is longer than layerStates

PiperOrigin-RevId: 307708653

1 files changed, 25 insertions, 8 deletions

diff --git a/test/packetimpact/testbench/connections.go b/test/packetimpact/testbench/connections.go
index f84fd8ba7..00a366894 100644
--- a/test/packetimpact/testbench/connections.go
+++ b/test/packetimpact/testbench/connections.go
@@ -363,16 +363,33 @@ type Connection struct {
 // reverse is never a match. override overrides the default matchers for each
 // Layer.
 func (conn *Connection) match(override, received Layers) bool {
-	if len(received) < len(conn.layerStates) {
+	var layersToMatch int
+	if len(override) < len(conn.layerStates) {
+		layersToMatch = len(conn.layerStates)
+	} else {
+		layersToMatch = len(override)
+	}
+	if len(received) < layersToMatch {
 		return false
 	}
-	for i, s := range conn.layerStates {
-		toMatch := s.incoming(received[i])
-		if toMatch == nil {
-			return false
-		}
-		if i < len(override) {
-			toMatch.merge(override[i])
+	for i := 0; i < layersToMatch; i++ {
+		var toMatch Layer
+		if i < len(conn.layerStates) {
+			s := conn.layerStates[i]
+			toMatch = s.incoming(received[i])
+			if toMatch == nil {
+				return false
+			}
+			if i < len(override) {
+				if err := toMatch.merge(override[i]); err != nil {
+					conn.t.Fatalf("failed to merge: %s", err)
+				}
+			}
+		} else {
+			toMatch = override[i]
+			if toMatch == nil {
+				conn.t.Fatalf("expect the overriding layers to be non-nil")
+			}
 		}
 		if !toMatch.match(received[i]) {
 			return false