Do not fail on $HOME not containing .config directory

Fixes: containers/podman#23818

Signed-off-by: Daniel J Walsh <[email protected]>

pkg/config/config_test.go

@@ -14,6 +14,7 @@ import (
 	"github.com/onsi/gomega"
 	selinux "github.com/opencontainers/selinux/go-selinux"
 	"github.com/sirupsen/logrus"
+	oscaps "github.com/syndtr/gocapability/capability"
 )
 
 var _ = Describe("Config", func() {
@@ -847,6 +848,28 @@ env=["foo=bar"]`
 		gomega.Expect(config.Containers.EnableLabeledUsers).To(gomega.BeTrue())
 	})
 
+	It("HomeDirTest", func() {
+		oldHOMEDIR, set := os.LookupEnv("HOME")
+		dir, err := os.MkdirTemp("", "configTest")
+		gomega.Expect(err).ToNot(gomega.HaveOccurred())
+		defer os.RemoveAll(dir)
+		os.Chmod(dir, 0o000)
+		caps, err := oscaps.NewPid2(0)
+		gomega.Expect(err).ToNot(gomega.HaveOccurred())
+		caps.Unset(oscaps.EFFECTIVE, oscaps.CAP_DAC_OVERRIDE)
+		defer caps.Set(oscaps.EFFECTIVE, oscaps.CAP_DAC_OVERRIDE)
+
+		os.Setenv("HOME", dir)
+		_, err = defaultConfig()
+		gomega.Expect(err).ToNot(gomega.HaveOccurred())
+
+		if set {
+			os.Setenv("HOME", oldHOMEDIR)
+		} else {
+			os.Unsetenv("HOME")
+		}
+	})
+
 	It("ParsePullPolicy", func() {
 		for _, test := range []struct {
 			value  string

pkg/config/default.go

@@ -3,6 +3,7 @@ package config
 import (
 	"errors"
 	"fmt"
+	"io/fs"
 	"net"
 	"os"
 	"path/filepath"
@@ -188,6 +189,23 @@ const (
 	DefaultVolumePluginTimeout = 5
 )
 
+func defaultSigPath() (string, error) {
+	// NOTE: For now we want Windows to use system locations.
+	// GetRootlessUID == -1 on Windows, so exclude negative range
+	if unshare.GetRootlessUID() > 0 {
+		configHome, err := homedir.GetConfigHome()
+		if err == nil {
+			sigPath := filepath.Join(configHome, DefaultRootlessSignaturePolicyPath)
+			if err := fileutils.Exists(sigPath); err == nil {
+				return sigPath, nil
+			}
+		} else if !errors.Is(err, fs.ErrNotExist) {
+			return "", err
+		}
+	}
+	return DefaultSignaturePolicyPath, nil
+}
+
 // defaultConfig returns Config with builtin defaults and minimal adjustments
 // to the current host only. It does not read any config files from the host or
 // the environment.
@@ -197,22 +215,11 @@ func defaultConfig() (*Config, error) {
 		return nil, err
 	}
 
-	defaultEngineConfig.SignaturePolicyPath = DefaultSignaturePolicyPath
-	// NOTE: For now we want Windows to use system locations.
-	// GetRootlessUID == -1 on Windows, so exclude negative range
-	if unshare.GetRootlessUID() > 0 {
-		configHome, err := homedir.GetConfigHome()
-		if err != nil {
-			return nil, err
-		}
-		sigPath := filepath.Join(configHome, DefaultRootlessSignaturePolicyPath)
-		defaultEngineConfig.SignaturePolicyPath = sigPath
-		if err := fileutils.Exists(sigPath); err != nil {
-			if err := fileutils.Exists(DefaultSignaturePolicyPath); err == nil {
-				defaultEngineConfig.SignaturePolicyPath = DefaultSignaturePolicyPath
-			}
-		}
+	sigPath, err := defaultSigPath()
+	if err != nil {
+		return nil, err
 	}
+	defaultEngineConfig.SignaturePolicyPath = sigPath
 
 	cgroupNS := "host"
 	if cgroup2, _ := cgroupv2.Enabled(); cgroup2 {