1 files changed, 6 insertions, 2 deletions
diff --git a/src/libsystemd/sd-bus/bus-signature.c b/src/libsystemd/sd-bus/bus-signature.c
index 18c91e8707..1ecd6e8b7e 100644
--- a/src/libsystemd/sd-bus/bus-signature.c
+++ b/src/libsystemd/sd-bus/bus-signature.c
@@ -1,6 +1,4 @@
 /* SPDX-License-Identifier: LGPL-2.1+ */
-/***
-***/
 
 #include <util.h>
 
@@ -58,6 +56,12 @@ static int signature_element_length_internal(
                         p += t;
                 }
 
+                if (p - s < 2)
+                        /* D-Bus spec: Empty structures are not allowed; there
+                         * must be at least one type code between the parentheses.
+                         */
+                        return -EINVAL;
+
                 *l = p - s + 1;
                 return 0;
         }