fix(cache): address race condition, resource leak, and path traversal

- Fix race condition in cache.Store: hold lock during persist to ensure
  snapshot consistency with disk writes
- Fix resource leak in syncDir: use defer to ensure directory fd is closed
- Add path traversal validation in teamloader: prevent cache paths from
  escaping parent directory using filepath.Clean and prefix check
- Add test for path traversal protection

Assisted-By: docker-agent

pkg/cache/cache.go

@@ -121,14 +121,10 @@ func (c *cache) Store(question, response string) {
 	key := c.normalize(question)
 
 	c.mu.Lock()
+	defer c.mu.Unlock()
 	c.entries[key] = response
-	var snapshot map[string]string
-	if c.persist != nil {
-		snapshot = maps.Clone(c.entries)
-	}
-	c.mu.Unlock()
-
 	if c.persist != nil {
+		snapshot := maps.Clone(c.entries)
 		c.persist(snapshot)
 	}
 }
@@ -220,6 +216,6 @@ func syncDir(dir string) {
 	if err != nil {
 		return
 	}
+	defer d.Close()
 	_ = d.Sync()
-	_ = d.Close()
 }

pkg/teamloader/teamloader.go

@@ -174,6 +174,12 @@ func LoadWithConfig(ctx context.Context, agentSource config.Source, runConfig *c
 			cachePath := agentConfig.Cache.Path
 			if cachePath != "" && !filepath.IsAbs(cachePath) {
 				cachePath = filepath.Join(parentDir, cachePath)
+				cachePath = filepath.Clean(cachePath)
+				// Ensure the resolved path is within parentDir to prevent path traversal
+				cleanParent := filepath.Clean(parentDir) + string(filepath.Separator)
+				if !strings.HasPrefix(cachePath+string(filepath.Separator), cleanParent) {
+					return nil, fmt.Errorf("agent %q: cache path %q escapes parent directory", agentConfig.Name, agentConfig.Cache.Path)
+				}
 			}
 			c, err := cache.New(cache.Config{
 				Enabled:       true,

pkg/teamloader/teamloader_test.go

@@ -483,3 +483,29 @@ func TestExternalDepthContext(t *testing.T) {
 	ctx = contextWithExternalDepth(ctx, 7)
 	assert.Equal(t, 7, externalDepthFromContext(ctx))
 }
+
+func TestLoadWithConfig_CachePathTraversal(t *testing.T) {
+	tmpDir := t.TempDir()
+
+	// Create a config file with a path traversal attempt
+	configPath := filepath.Join(tmpDir, "agent.yaml")
+	configContent := `
+agents:
+  root:
+    model: openai/gpt-4o
+    description: Test agent
+    instruction: You are a test agent.
+    cache:
+      enabled: true
+      path: ../../../../etc/passwd
+`
+	require.NoError(t, os.WriteFile(configPath, []byte(configContent), 0o600))
+
+	source := config.NewFileSource(configPath)
+	runConfig := &config.RuntimeConfig{}
+	runConfig.WorkingDir = tmpDir
+
+	_, err := LoadWithConfig(t.Context(), source, runConfig)
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), "escapes parent directory")
+}