add fuzz test for (signature) decoding

Author: guelfey

proto_fuzz_test.go

@@ -0,0 +1,25 @@
+//go:build go1.18
+// +build go1.18
+
+package dbus
+
+import (
+	"bytes"
+	"encoding/binary"
+	"testing"
+)
+
+func FuzzProto(f *testing.F) {
+	for _, t := range protoTests {
+		f.Add(t.bigEndian, SignatureOf(t.vs...).str)
+		f.Add(t.littleEndian, SignatureOf(t.vs...).str)
+	}
+	f.Fuzz(func(t *testing.T, buf []byte, sigStr string) {
+		sig, err := ParseSignature(sigStr)
+		if err != nil {
+			return
+		}
+		bigDec := newDecoder(bytes.NewReader(buf), binary.BigEndian, make([]int, 0))
+		_, _ = bigDec.Decode(sig)
+	})
+}

testdata/fuzz/FuzzProto/55fb6653b98fd09c839000a246acaabd9bd977bd526d7bb79ff949d848716fb6

@@ -0,0 +1,3 @@
+go test fuzz v1
+[]byte("0")
+string("a{}")