From 55e0929fab461fee7733a18f8b543f9a5d6b9f6f Mon Sep 17 00:00:00 2001
From: Aleksandr Nogikh <nogikh@google.com>
Date: Thu, 6 Feb 2025 15:06:26 +0100
Subject: all: enable run_fsck by default

Check for the existence of fsck binaries and report their absence only
once.
---
 pkg/image/fsck.go       | 26 ++++++++++++++++++++++++++
 pkg/image/fsck_test.go  |  9 ++-------
 pkg/mgrconfig/config.go |  1 +
 pkg/mgrconfig/load.go   |  1 +
 syz-manager/manager.go  |  6 ++++--
 5 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/pkg/image/fsck.go b/pkg/image/fsck.go
index e749871f9..fbaeca9c4 100644
--- a/pkg/image/fsck.go
+++ b/pkg/image/fsck.go
@@ -11,7 +11,9 @@ import (
 	"os/exec"
 	"strconv"
 	"strings"
+	"sync"
 
+	"github.com/google/syzkaller/pkg/log"
 	"github.com/google/syzkaller/pkg/osutil"
 )
 
@@ -59,3 +61,27 @@ func Fsck(r io.Reader, fsckCmd string) ([]byte, bool, error) {
 	prefix := fsckCmd + " exited with status code " + strconv.Itoa(exitCode) + "\n"
 	return append([]byte(prefix), output...), exitCode == 0, nil
 }
+
+type FsckChecker struct {
+	mu     sync.Mutex
+	exists map[string]bool
+}
+
+func (fc *FsckChecker) Exists(cmd string) bool {
+	fc.mu.Lock()
+	defer fc.mu.Unlock()
+	bin := strings.Fields(cmd)[0]
+	if ret, ok := fc.exists[bin]; ok {
+		return ret
+	}
+	if fc.exists == nil {
+		fc.exists = map[string]bool{}
+	}
+	_, err := exec.LookPath(bin)
+	found := err == nil
+	if !found {
+		log.Logf(0, "%s not found, images won't be checked", bin)
+	}
+	fc.exists[bin] = found
+	return found
+}
diff --git a/pkg/image/fsck_test.go b/pkg/image/fsck_test.go
index aae102ec7..e901e089f 100644
--- a/pkg/image/fsck_test.go
+++ b/pkg/image/fsck_test.go
@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"os/exec"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -24,16 +23,12 @@ import (
 
 const corruptedFs = "IAmACorruptedFs"
 
-func fsckAvailable(cmd string) bool {
-	_, err := exec.LookPath(strings.Fields(cmd)[0])
-	return err == nil
-}
-
 func TestFsck(t *testing.T) {
 	target, err := prog.GetTarget(targets.Linux, targets.AMD64)
 	if err != nil {
 		t.Fatal(err)
 	}
+	fsckChecker := FsckChecker{}
 
 	// Use the images generated by syz-imagegen as a collection of clean file systems.
 	cleanFsProgs, err := filepath.Glob(filepath.Join("..", "sys", "linux", "test", "syz_mount_image_*_0"))
@@ -56,7 +51,7 @@ func TestFsck(t *testing.T) {
 			}
 			fsckCmd := c.Meta.Attrs.Fsck
 			// Tolerate missing fsck commands except during CI runs.
-			skip := !fsckAvailable(fsckCmd) && os.Getenv("CI") == ""
+			skip := !fsckChecker.Exists(fsckCmd) && os.Getenv("CI") == ""
 
 			fsName := strings.TrimPrefix(c.Meta.Name, "syz_mount_image$")
 			// Check that the file system in the image is detected as clean.
diff --git a/pkg/mgrconfig/config.go b/pkg/mgrconfig/config.go
index a02c00c67..42730eef4 100644
--- a/pkg/mgrconfig/config.go
+++ b/pkg/mgrconfig/config.go
@@ -206,6 +206,7 @@ type Config struct {
 	// Note: you may need to install 3rd-party dependencies for this to work.
 	// fsck commands that can be run by syz-manager are specified in mount
 	// syscall descriptions - typically in sys/linux/filesystem.txt.
+	// Enabled by default.
 	RunFsck bool `json:"run_fsck"`
 
 	// Type of virtual machine to use, e.g. "qemu", "gce", "android", "isolated", etc.
diff --git a/pkg/mgrconfig/load.go b/pkg/mgrconfig/load.go
index 0624dae00..81ff2871a 100644
--- a/pkg/mgrconfig/load.go
+++ b/pkg/mgrconfig/load.go
@@ -94,6 +94,7 @@ func defaultValues() *Config {
 		MaxCrashLogs:   100,
 		Procs:          6,
 		PreserveCorpus: true,
+		RunFsck:        true,
 		Experimental: Experimental{
 			RemoteCover:      true,
 			CoverEdges:       true,
diff --git a/syz-manager/manager.go b/syz-manager/manager.go
index fdb4929d7..b0354ea61 100644
--- a/syz-manager/manager.go
+++ b/syz-manager/manager.go
@@ -106,6 +106,7 @@ type Manager struct {
 	benchFile *os.File
 
 	assetStorage *asset.Storage
+	fsckChecker  image.FsckChecker
 
 	reproLoop *manager.ReproLoop
 
@@ -944,10 +945,11 @@ func (mgr *Manager) uploadReproAssets(repro *repro.Result) []dashapi.NewAsset {
 			return
 		}
 		// Report file systems that fail fsck with a separate tag.
-		if mgr.cfg.RunFsck && dashTyp == dashapi.MountInRepro && c.Meta.Attrs.Fsck != "" {
+		if mgr.cfg.RunFsck && dashTyp == dashapi.MountInRepro &&
+			c.Meta.Attrs.Fsck != "" && mgr.fsckChecker.Exists(c.Meta.Attrs.Fsck) {
 			logs, isClean, err := image.Fsck(r2, c.Meta.Attrs.Fsck)
 			if err != nil {
-				log.Logf(1, "fsck of the asset %v failed: %v", name, err)
+				log.Errorf("fsck of the asset %v failed: %v", name, err)
 			} else {
 				asset.FsckLog = logs
 				asset.FsIsClean = isClean
-- 
cgit mrf-deployment