diff --git a/syscall/linux/constants.lua b/syscall/linux/constants.lua
index 23c68af3f3..a1b5c3dcbc 100644
--- a/syscall/linux/constants.lua
+++ b/syscall/linux/constants.lua
@@ -1162,6 +1162,10 @@ c.RTA = strflag {
   MP_ALGO = 14,
   TABLE = 15,
   MARK = 16,
+  MFC_STATS = 17,
+  VIA = 18,
+  NEWDST = 19,
+  PREF = 20,
 }
 
 -- route flags
diff --git a/syscall/linux/nl.lua b/syscall/linux/nl.lua
index fad5625ed8..20c4dcbb0b 100644
--- a/syscall/linux/nl.lua
+++ b/syscall/linux/nl.lua
@@ -173,6 +173,10 @@ local rta_decode = {
     ir.cacheinfo = t.rta_cacheinfo()
     ffi.copy(ir.cacheinfo, buf, s.rta_cacheinfo)
   end,
+  [c.RTA.PREF] = function(ir, buf, len)
+    local i = pt.uint8(buf)
+    ir.pref = tonumber(i[0])
+  end,
   -- TODO some missing
 }