[PATCH v3 5/5] host/rootfs: Try to protect the portal and dbus daemon

Demi Marie Obenour
2025-12-03T15:56:03Z

This tries to protect the portal and D-Bus daemon from other processes.
Unfortunately, this protection is extremely limited: it currently only
switches network and cgroup namespaces.

The single biggest improvement that could be made, by far, is to make
all mounts that the portal and bus daemon have access to 'nosymfollow',
except for the root filesystem. Unfortunately, I am not aware of how to
enforce this on mounts that appear after the service starts.

Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
---
.../run-image/service/vm-services/template/data/service/dbus/run | 1 +
1 file changed, 1 insertion(+)

diff --git a/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/dbus/run b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/dbus/run
index 9b2319265024ab51934157834b280be869afa9b9..4e100ad39e11c802f875ac318c2d908b5e6dd9b8 100755
--- a/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/dbus/run
+++ b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/dbus/run
@@ -6,6 +6,7 @@ importas -i VM VM

nsenter --mount=${VM}/mount

+unshare --net --ipc
dbus-daemon
--config-file /usr/share/dbus-1/session.conf
--print-address 3

--
2.52.0