diff --git a/pkgs/additional/sanebox/sanebox b/pkgs/additional/sanebox/sanebox
index 33d51bf6..51c9cd70 100755
--- a/pkgs/additional/sanebox/sanebox
+++ b/pkgs/additional/sanebox/sanebox
@@ -122,7 +122,7 @@ usage() {
   echo '  --sanebox-no-portal'
   echo '      undo a previous `--sanebox-portal` arg'
   echo '  --sanebox-bwrap-arg <arg>'
-  echo '  --sanebox-net-dev <iface>'
+  echo '  --sanebox-net-dev <iface>|all'
   echo '  --sanebox-net-gateway <ip-address>'
   echo '  --sanebox-dns <server>'
   echo '  --sanebox-keep-namespace <cgroup|ipc|pid|uts|all>'