[release-4.20] OCPBUGS-77416: Fix registriesd "unknown userid" failure for arbitrary UIDs

v2/internal/pkg/registriesd/registriesd.go

@@ -4,7 +4,6 @@ import (
 	"errors"
 	"fmt"
 	"os"
-	"os/user"
 	"path/filepath"
 	"strings"
 
@@ -49,12 +48,16 @@ func PrepareRegistrydCustomDir(workingDir, registriesDirPath string, registryHos
 }
 
 func GetDefaultRegistrydConfigPath() (string, error) {
-	usr, err := user.Current()
-	if err != nil {
-		return "", fmt.Errorf("unable to determine the current user : %w", err)
+	// Use os.UserHomeDir() instead of user.Current() to support containerized
+	// environments with arbitrary UIDs that don't exist in /etc/passwd.
+	// os.UserHomeDir() reads $HOME env var first, avoiding passwd lookups.
+	homeDir, err := os.UserHomeDir()
+	if err == nil {
+		return registriesDirPathWithHomeDir(homeDir), nil
 	}
 
-	return registriesDirPathWithHomeDir(usr.HomeDir), nil
+	// Fall back to system default if home directory cannot be determined.
+	return systemRegistriesDirPath, nil
 }
 
 func registriesDirPathWithHomeDir(homeDir string) string {

v2/internal/pkg/registriesd/registriesd_test.go

@@ -1,6 +1,7 @@
 package registriesd
 
 import (
+	"os"
 	"path/filepath"
 	"testing"
 
@@ -44,3 +45,22 @@ func TestGetCustomRegistrydConfigPath(t *testing.T) {
 	expectedRegistriesD := filepath.Join(testFolder, "containers/registries.d")
 	assert.Equal(t, expectedRegistriesD, registriesDirPath)
 }
+
+func TestGetDefaultRegistrydConfigPath(t *testing.T) {
+	testHome := t.TempDir()
+	t.Setenv("HOME", testHome)
+
+	// When user registries.d doesn't exist, should return system path
+	path, err := GetDefaultRegistrydConfigPath()
+	assert.NoError(t, err)
+	assert.Equal(t, systemRegistriesDirPath, path)
+
+	// When user registries.d exists, should return user path
+	expectedUserPath := filepath.Join(testHome, ".config/containers/registries.d")
+	err = os.MkdirAll(expectedUserPath, 0755)
+	assert.NoError(t, err)
+
+	path, err = GetDefaultRegistrydConfigPath()
+	assert.NoError(t, err)
+	assert.Equal(t, expectedUserPath, path)
+}