csource: force enable tun flag when required

1 files changed, 16 insertions, 0 deletions

diff --git a/csource/csource.go b/csource/csource.go
index ccc235f7e..0a5bcddd7 100644
--- a/csource/csource.go
+++ b/csource/csource.go
@@ -42,6 +42,18 @@ type Options struct {
 	Repro bool
 }
 
+func RequiresTun(p *prog.Prog) bool {
+	for _, c := range p.Calls {
+		switch c.Meta.CallName {
+		case "syz_emit_ethernet":
+			return true
+		case "syz_extract_tcp_seq":
+			return true
+		}
+	}
+	return false
+}
+
 func Write(p *prog.Prog, opts Options) ([]byte, error) {
 	exec := make([]byte, prog.ExecBufferSize)
 	if err := p.SerializeForExec(exec, 0); err != nil {
@@ -49,6 +61,10 @@ func Write(p *prog.Prog, opts Options) ([]byte, error) {
 	}
 	w := new(bytes.Buffer)
 
+	if RequiresTun(p) {
+		opts.EnableTun = true
+	}
+
 	fmt.Fprint(w, "// autogenerated by syzkaller (http://github.com/google/syzkaller)\n\n")
 
 	handled := make(map[string]int)