From: Georges Discry <georges@discry.be>
Date: Thu, 20 Apr 2023 20:09:34 +0000 (+0200)
Subject: Check if already root in become_root
X-Git-Tag: v15~221^2~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=49b72a8ab72f7ad256b45e965cb0f4efa3833bfe;p=thirdparty%2Fmkosi.git

Check if already root in become_root

Instead of requiring the check for `os.getuid() != 0` before calling
`mkosi.run.become_root()`, that check is now performed at the beginning
with an early return if the user is already root.
---

diff --git a/mkosi/__init__.py b/mkosi/__init__.py
index 12db7bfbe..d3d066638 100644
--- a/mkosi/__init__.py
+++ b/mkosi/__init__.py
@@ -2412,8 +2412,7 @@ def run_verb(config: MkosiConfig) -> None:
 
         if needs_build(config) or config.verb == Verb.clean:
             def target() -> None:
-                if os.getuid() != 0:
-                    become_root()
+                become_root()
                 unlink_output(config)
 
             fork_and_wait(target)
@@ -2421,7 +2420,7 @@ def run_verb(config: MkosiConfig) -> None:
         if needs_build(config):
             def target() -> None:
                 # Get the user UID/GID either on the host or in the user namespace running the build
-                uid, gid = become_root() if os.getuid() != 0 else current_user_uid_gid()
+                uid, gid = become_root()
                 init_mount_namespace()
                 build_stuff(uid, gid, config)
 
diff --git a/mkosi/run.py b/mkosi/run.py
index 0a527ad34..90e935d54 100644
--- a/mkosi/run.py
+++ b/mkosi/run.py
@@ -13,7 +13,7 @@ from pathlib import Path
 from types import TracebackType
 from typing import Any, Callable, Mapping, Optional, Sequence, Type, TypeVar
 
-from mkosi.backend import MkosiState
+from mkosi.backend import MkosiState, current_user_uid_gid
 from mkosi.log import ARG_DEBUG, MkosiPrinter, die
 from mkosi.types import _FILE, CompletedProcess, PathString, Popen
 
@@ -66,6 +66,8 @@ def become_root() -> tuple[int, int]:
 
     The function returns the UID-GID pair of the invoking user in the namespace (65436, 65436).
     """
+    if os.getuid() == 0:
+        return current_user_uid_gid()
     subuid = read_subrange(Path("/etc/subuid"))
     subgid = read_subrange(Path("/etc/subgid"))