diff --git a/include/uapi/linux/if_tun.h b/include/uapi/linux/if_tun.h
index 79d53c7a1ebd..a0ddc50a7534 100644
--- a/include/uapi/linux/if_tun.h
+++ b/include/uapi/linux/if_tun.h
@@ -69,6 +69,10 @@
 #define IFF_NAPI_FRAGS	0x0020
 /* Used in TUNSETIFF to bring up tun/tap without carrier */
 #define IFF_NO_CARRIER	0x0040
+/* Stop the queue instead of dropping when the internal ring is full, so an
+ * attached qdisc applies backpressure instead of being bypassed.
+ */
+#define IFF_BACKPRESSURE	0x0080
 #define IFF_NO_PI	0x1000
 /* This flag has no real effect */
 #define IFF_ONE_QUEUE	0x2000
diff --git a/tools/include/uapi/linux/if_tun.h b/tools/include/uapi/linux/if_tun.h
index 2ec07de1d73b..2c85525704c1 100644
--- a/tools/include/uapi/linux/if_tun.h
+++ b/tools/include/uapi/linux/if_tun.h
@@ -67,6 +67,10 @@
 #define IFF_TAP		0x0002
 #define IFF_NAPI	0x0010
 #define IFF_NAPI_FRAGS	0x0020
+/* Stop the queue instead of dropping when the internal ring is full, so an
+ * attached qdisc applies backpressure instead of being bypassed.
+ */
+#define IFF_BACKPRESSURE	0x0080
 #define IFF_NO_PI	0x1000
 /* This flag has no real effect */
 #define IFF_ONE_QUEUE	0x2000