fix(cmd): prevent adding connection with invalid identities file

Fixes #26016

Signed-off-by: axel7083 <[email protected]>

Author: axel7083

cmd/podman/system/connection/add.go

@@ -141,6 +141,19 @@ func add(cmd *cobra.Command, args []string) error {
 
 	switch uri.Scheme {
 	case "ssh":
+		// ensure the Identity provided is a valid file
+		info, err := os.Stat(entities.Identity)
+		switch {
+		case errors.Is(err, os.ErrNotExist):
+			logrus.Warnf("%q does not exist", entities.Identity)
+		case errors.Is(err, os.ErrPermission):
+			logrus.Warnf("You do not have permission to read %q", entities.Identity)
+		case err != nil:
+			return err
+		case info.IsDir():
+			return fmt.Errorf("%q is a directory", entities.Identity)
+		}
+
 		return ssh.Create(entities, sshMode)
 	case "unix":
 		if cmd.Flags().Changed("identity") {