diff --git a/include/linux/sock_diag.h b/include/linux/sock_diag.h
index db4bae7..6793fac 100644
--- a/include/linux/sock_diag.h
+++ b/include/linux/sock_diag.h
@@ -18,6 +18,7 @@
 	SK_MEMINFO_FWD_ALLOC,
 	SK_MEMINFO_WMEM_QUEUED,
 	SK_MEMINFO_OPTMEM,
+	SK_MEMINFO_BACKLOG,
 
 	SK_MEMINFO_VARS,
 };