diff --git a/libc/kernel/uapi/linux/sysctl.h b/libc/kernel/uapi/linux/sysctl.h
index ebaf8a9..ae9c2ba 100644
--- a/libc/kernel/uapi/linux/sysctl.h
+++ b/libc/kernel/uapi/linux/sysctl.h
@@ -407,6 +407,7 @@
   NET_IPV4_CONF_PROMOTE_SECONDARIES = 20,
   NET_IPV4_CONF_ARP_ACCEPT = 21,
   NET_IPV4_CONF_ARP_NOTIFY = 22,
+  NET_IPV4_CONF_ARP_EVICT_NOCARRIER = 23,
 };
 enum {
   NET_IPV4_NF_CONNTRACK_MAX = 1,