From 2dd3466a78eaefe3646eb728e806a0f3fe175553 Mon Sep 17 00:00:00 2001
From: Lubomir Rintel <lkundrak@v3.sk>
Date: Tue, 29 Oct 2024 16:37:52 +0100
Subject: [PATCH] data/NetworkManager.service: restrict the unit some more
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This adds some low-hanging food to improve our score with "systemd-analyze
security" by one point:

Before:
  → Overall exposure level for NetworkManager.service: 7.8 EXPOSED 🙁

After:
  → Overall exposure level for NetworkManager.service: 6.8 MEDIUM 😐

Nothing particularly impactful here: we still got DAC_OVERRIDE, we still
can insert loadable modules (as opposed to relying on autoload) and
read user home directories. But there's a slight chance this may save
our butts one day, who knows.

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/2062
---
 data/NetworkManager.service.in | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/data/NetworkManager.service.in b/data/NetworkManager.service.in
index 8cd2ac87a3..995c1e787c 100644
--- a/data/NetworkManager.service.in
+++ b/data/NetworkManager.service.in
@@ -21,8 +21,17 @@ TimeoutStartSec=600
 
 CapabilityBoundingSet=CAP_NET_ADMIN CAP_DAC_OVERRIDE CAP_NET_RAW CAP_NET_BIND_SERVICE CAP_SETGID CAP_SETUID CAP_SYS_MODULE CAP_AUDIT_WRITE CAP_KILL CAP_SYS_CHROOT
 
-ProtectSystem=true
+PrivateTmp=true
+
+ProtectClock=true
+ProtectControlGroups=true
 ProtectHome=read-only
+ProtectKernelLogs=true
+ProtectSystem=true
+
+RestrictNamespaces=cgroup ipc net mnt pid user uts
+RestrictRealtime=true
+RestrictSUIDSGID=true
 
 # We require file descriptors for DHCP etc. When activating many interfaces,
 # the default limit of 1024 is easily reached.