tools/syz-prog2c: add vmlinux parsing stage for KFuzzTest

If vmlinux is specified as a flag, we perform a setup stage where we
parse vmlinux for KFuzzTest targets.

Author: Ethan Graham

tools/syz-prog2c/prog2c.go

@@ -11,6 +11,7 @@ import (
 	"runtime"
 
 	"github.com/google/syzkaller/pkg/csource"
+	"github.com/google/syzkaller/pkg/kfuzztest"
 	"github.com/google/syzkaller/prog"
 	_ "github.com/google/syzkaller/sys"
 )
@@ -33,6 +34,7 @@ var (
 	flagLeak       = flag.Bool("leak", false, "do leak checking")
 	flagEnable     = flag.String("enable", "none", "enable only listed additional features")
 	flagDisable    = flag.String("disable", "none", "enable all additional features except listed")
+	flagVmlinux    = flag.String("vmlinux", "", "path to vmlinux binary (required for dynamically discovered calls")
 )
 
 func main() {
@@ -54,6 +56,13 @@ func main() {
 		fmt.Fprintf(os.Stderr, "%v\n", err)
 		os.Exit(1)
 	}
+	if *flagVmlinux != "" {
+		_, err = kfuzztest.ActivateKFuzzTargets(target, *flagVmlinux)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "%v\n", err)
+			os.Exit(1)
+		}
+	}
 	data, err := os.ReadFile(*flagProg)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "failed to read prog file: %v\n", err)