bus: refuse messages pretending to originate from local interface

diff --git a/src/libsystemd-bus/bus-message.c b/src/libsystemd-bus/bus-message.c
index d6888738e1063989594f2bc762146551f16a3925..b0f4b16d41ad726fef73077eb88ca9bcfaf9af09 100644 (file)
--- a/src/libsystemd-bus/bus-message.c
+++ b/src/libsystemd-bus/bus-message.c
@@ -5133,6 +5133,14 @@ int bus_message_parse_fields(sd_bus_message *m) {
                 break;
         }
 
+        /* Refuse non-local messages that claim they are local */
+        if (streq_ptr(m->path, "/org/freedesktop/DBus/Local"))
+                return -EBADMSG;
+        if (streq_ptr(m->interface, "org.freedesktop.DBus.Local"))
+                return -EBADMSG;
+        if (streq_ptr(m->sender, "org.freedesktop.DBus.Local"))
+                return -EBADMSG;
+
         m->root_container.end = BUS_MESSAGE_BODY_SIZE(m);
 
         if (BUS_MESSAGE_IS_GVARIANT(m)) {