diff --git a/src/libsystemd/sd-journal/sd-journal.c b/src/libsystemd/sd-journal/sd-journal.c
index 659e1e4e34..9947947ef2 100644
--- a/src/libsystemd/sd-journal/sd-journal.c
+++ b/src/libsystemd/sd-journal/sd-journal.c
@@ -2164,18 +2164,16 @@ _public_ void sd_journal_close(sd_journal *j) {
 }
 
 _public_ int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *ret) {
-        Object *o;
         JournalFile *f;
+        Object *o;
         int r;
 
         assert_return(j, -EINVAL);
         assert_return(!journal_pid_changed(j), -ECHILD);
-        assert_return(ret, -EINVAL);
 
         f = j->current_file;
         if (!f)
                 return -EADDRNOTAVAIL;
-
         if (f->current_offset <= 0)
                 return -EADDRNOTAVAIL;
 
@@ -2183,7 +2181,13 @@ _public_ int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *ret) {
         if (r < 0)
                 return r;
 
-        *ret = le64toh(o->entry.realtime);
+        uint64_t t = le64toh(o->entry.realtime);
+        if (!VALID_REALTIME(t))
+                return -EBADMSG;
+
+        if (ret)
+                *ret = t;
+
         return 0;
 }