all: enable run_fsck by default

Check for the existence of fsck binaries and report their absence only
once.

2 files changed, 28 insertions, 7 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.