pkg/instance: explicitly specify optional fuzzer arguments

Otherwise we get problems while testing patches for older syzkaller
versions, which didn't support optional arguments.

Adjust tests so that problems with how OldFuzzerCmd handles such
arguments could be seen.

2 files changed, 18 insertions, 13 deletions

diff --git a/pkg/instance/instance.go b/pkg/instance/instance.go
index c225f9696..e670a2c64 100644
--- a/pkg/instance/instance.go
+++ b/pkg/instance/instance.go
@@ -437,6 +437,11 @@ func (inst *inst) testProgram(command string, testTime time.Duration) error {
 	return &CrashError{Report: rep}
 }
 
+type OptionalFuzzerArgs struct {
+	Slowdown int
+	RawCover bool
+}
+
 type FuzzerCmdArgs struct {
 	Fuzzer    string
 	Executor  string
@@ -451,8 +456,7 @@ type FuzzerCmdArgs struct {
 	Debug     bool
 	Test      bool
 	Runtest   bool
-	Slowdown  int
-	RawCover  bool
+	Optional  *OptionalFuzzerArgs
 }
 
 func FuzzerCmd(args *FuzzerCmdArgs) string {
@@ -471,16 +475,13 @@ func FuzzerCmd(args *FuzzerCmdArgs) string {
 	if args.Verbosity != 0 {
 		verbosityArg = fmt.Sprintf(" -vv=%v", args.Verbosity)
 	}
-	flags := []tool.Flag{}
-	if args.Slowdown > 0 {
-		flags = append(flags, tool.Flag{Name: "slowdown", Value: fmt.Sprint(args.Slowdown)})
-	}
-	if args.RawCover {
-		flags = append(flags, tool.Flag{Name: "raw_cover", Value: "true"})
-	}
 	optionalArg := ""
-	if len(flags) > 0 {
-		optionalArg += " " + tool.OptionalFlags(flags)
+	if args.Optional != nil {
+		flags := []tool.Flag{
+			{Name: "slowdown", Value: fmt.Sprint(args.Optional.Slowdown)},
+			{Name: "raw_cover", Value: fmt.Sprint(args.Optional.RawCover)},
+		}
+		optionalArg = " " + tool.OptionalFlags(flags)
 	}
 	return fmt.Sprintf("%v -executor=%v -name=%v -arch=%v%v -manager=%v -sandbox=%v"+
 		" -procs=%v -cover=%v -debug=%v -test=%v%v%v%v",
@@ -490,10 +491,14 @@ func FuzzerCmd(args *FuzzerCmdArgs) string {
 
 func OldFuzzerCmd(fuzzer, executor, name, OS, arch, fwdAddr, sandbox string, procs int,
 	cover, test, optionalFlags bool, slowdown int) string {
+	var optional *OptionalFuzzerArgs
+	if optionalFlags {
+		optional = &OptionalFuzzerArgs{Slowdown: slowdown}
+	}
 	return FuzzerCmd(&FuzzerCmdArgs{Fuzzer: fuzzer, Executor: executor, Name: name,
 		OS: OS, Arch: arch, FwdAddr: fwdAddr, Sandbox: sandbox, Procs: procs,
 		Verbosity: 0, Cover: cover, Debug: false, Test: test, Runtest: false,
-		Slowdown: slowdown})
+		Optional: optional})
 }
 
 func ExecprogCmd(execprog, executor, OS, arch, sandbox string, repeat, threaded, collide bool,
diff --git a/pkg/instance/instance_test.go b/pkg/instance/instance_test.go
index 92903512c..2f5c08625 100644
--- a/pkg/instance/instance_test.go
+++ b/pkg/instance/instance_test.go
@@ -33,7 +33,7 @@ func TestFuzzerCmd(t *testing.T) {
 	flagDebug := flags.Bool("debug", false, "debug output from executor")
 	flagV := flags.Int("v", 0, "verbosity")
 	cmdLine := OldFuzzerCmd(os.Args[0], "/myexecutor", "myname", targets.Linux, targets.I386, "localhost:1234",
-		"namespace", 3, true, true, false, 0)
+		"namespace", 3, true, true, false, 5)
 	args := strings.Split(cmdLine, " ")[1:]
 	if err := flags.Parse(args); err != nil {
 		t.Fatal(err)