From 63bb64a056113d4be5fefb16604accf08c8c204a Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 25 Aug 2016 16:12:46 +0200 Subject: core: imply ProtectHome=read-only and ProtectSystem=strict if DynamicUser=1 Let's make sure that services that use DynamicUser=1 cannot leave files in the file system should the system accidentally have a world-writable directory somewhere. This effectively ensures that directories need to be whitelisted rather than blacklisted for access when DynamicUser=1 is set. --- src/core/unit.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'src') diff --git a/src/core/unit.c b/src/core/unit.c index de22f657c6..5d284a359d 100644 --- a/src/core/unit.c +++ b/src/core/unit.c @@ -3377,8 +3377,14 @@ int unit_patch_contexts(Unit *u) { return -ENOMEM; } + /* If the dynamic user option is on, let's make sure that the unit can't leave its UID/GID + * around in the file system or on IPC objects. Hence enforce a strict sandbox. */ + ec->private_tmp = true; ec->remove_ipc = true; + ec->protect_system = PROTECT_SYSTEM_STRICT; + if (ec->protect_home == PROTECT_HOME_NO) + ec->protect_home = PROTECT_HOME_READ_ONLY; } } -- cgit v1.2.3-54-g00ecf