prog: fix oob panic in rotatorState.Select

Reported-by: ManhNDd
Fixes #2372

2 files changed, 16 insertions, 0 deletions

diff --git a/prog/rotation.go b/prog/rotation.go
index 0171e6ace..544f22730 100644
--- a/prog/rotation.go
+++ b/prog/rotation.go
@@ -150,6 +150,9 @@ func (rs *rotatorState) Select() map[*Syscall]bool {
 	// However, a resource can be handled as dependency first, but then
 	// handled as top resource again. In such case we will still add calls
 	// that use this resource.
+	if len(rs.resources) == 0 {
+		return rs.Rotator.calls
+	}
 	for {
 		if len(rs.depQueue) == 0 && len(rs.calls) >= rs.goal || len(rs.calls) >= 2*rs.goal {
 			rs.calls, _ = rs.target.transitivelyEnabled(rs.calls)
diff --git a/prog/rotation_test.go b/prog/rotation_test.go
index 4a7aa31cc..e218a5eb6 100644
--- a/prog/rotation_test.go
+++ b/prog/rotation_test.go
@@ -9,8 +9,21 @@ import (
 	"math/rand"
 	"sort"
 	"testing"
+
+	"github.com/google/go-cmp/cmp"
 )
 
+func TestRotationResourceless(t *testing.T) {
+	target, rs, _ := initRandomTargetTest(t, "test", "64")
+	calls := map[*Syscall]bool{
+		target.SyscallMap["test$int"]: true,
+	}
+	got := MakeRotator(target, calls, rand.New(rs)).Select()
+	if diff := cmp.Diff(calls, got); diff != "" {
+		t.Fatal(diff)
+	}
+}
+
 func TestRotationRandom(t *testing.T) {
 	target, rs, _ := initTest(t)
 	for _, ncalls := range []int{10, 100, 1000, 1e9} {