bus_driver_handle_message: reject ActivationFailure if unprivileged

Specifically, this will allow ActivationFailure messages from our
own uid or from root, but reject them otherwise, even if the bus
configuration for who can own org.freedesktop.systemd1 is entirely
wrong due to something like CVE-2014-8148.

Signed-off-by: Simon McVittie <smcv@debian.org>
Reviewed-by: Colin Walters <walters@verbum.org>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=98157

diff --git a/bus/driver.c b/bus/driver.c
index 01fd340fffcd00aba541c44786c44d66757ce4d9..660f04d983d6f5569857300a0cd8f4dbfc5a932f 100644 (file)
--- a/bus/driver.c
+++ b/bus/driver.c
@@ -2616,6 +2616,15 @@ bus_driver_handle_message (DBusConnection *connection,
       BusContext *context;
       DBusConnection *systemd;
 
+      /* This is a directed signal, not a method call, so the log message
+       * is a little weird (it talks about "calling" ActivationFailure),
+       * but it's close enough */
+      if (!bus_driver_check_caller_is_privileged (connection,
+                                                  transaction,
+                                                  message,
+                                                  error))
+        return FALSE;
+
       context = bus_connection_get_context (connection);
       systemd = bus_driver_get_owner_of_name (connection,
           "org.freedesktop.systemd1");