2 files changed, 22 insertions, 12 deletions
diff --git a/kvmd/validators/kvm.py b/kvmd/validators/kvm.py
index 3a1c437b..df09d06e 100644
--- a/kvmd/validators/kvm.py
+++ b/kvmd/validators/kvm.py
@@ -20,17 +20,16 @@
 # ========================================================================== #
 
 
-import re
-
 from typing import Any
 
 from .. import keymap
 
-from . import check_not_none_string
 from . import check_string_in_list
 
 from .basic import valid_number
 
+from .os import valid_printable_filename
+
 
 # =====
 def valid_atx_power_action(arg: Any) -> str:
@@ -42,15 +41,7 @@ def valid_atx_button(arg: Any) -> str:
 
 
 def valid_msd_image_name(arg: Any) -> str:
-    if len(str(arg).strip()) == 0:
-        arg = None
-    arg = check_not_none_string(arg, "MSD image name", strip=True)
-    arg = re.sub(r"[^\w\.+@()\[\]-]", "_", arg)
-    if arg == ".":
-        arg = "_"
-    if arg == "..":
-        arg = "__"
-    return arg[:255]
+    return valid_printable_filename(arg, name="MSD image name")  # pragma: nocover
 
 
 def valid_log_seek(arg: Any) -> int:
diff --git a/kvmd/validators/os.py b/kvmd/validators/os.py
index 505df8e2..d37ae5d4 100644
--- a/kvmd/validators/os.py
+++ b/kvmd/validators/os.py
@@ -51,6 +51,25 @@ def valid_abs_path_exists(arg: Any, name: str="") -> str:
     return valid_abs_path(arg, exists=True, name=name)
 
 
+def valid_printable_filename(arg: Any, name: str="") -> str:
+    if not name:
+        name = "printable filename"
+
+    if len(str(arg).strip()) == 0:
+        arg = None
+    arg = check_not_none_string(arg, name)
+
+    if "/" in arg or "\0" in arg or arg in [".", ".."]:
+        raise_error(arg, name)
+
+    arg = "".join(
+        (ch if ch.isprintable() else "_")
+        for ch in arg[:255]
+    )
+    return arg
+
+
+# =====
 def valid_unix_mode(arg: Any) -> int:
     return int(valid_number(arg, min=0, name="UNIX mode"))