renumber: graceful error on invalid subnet

diff --git a/modules/renumber/renumber.lua b/modules/renumber/renumber.lua
index ccd320f632d358b58c0e769f0b3762953c2d80ff..c10063ca56ae781e54dc625738384d3068ee34c2 100644 (file)
--- a/modules/renumber/renumber.lua
+++ b/modules/renumber/renumber.lua
@@ -10,6 +10,7 @@ local function matchprefix(subnet, addr)
        local addrtype = string.find(addr, ':', 1, true) and kres.type.AAAA or kres.type.A
        local subnet_cd = ffi.new('char[16]')
        local bitlen = ffi.C.kr_straddr_subnet(subnet_cd, subnet)
+       if bitlen < 0 then error('[renumber] invalid subnet: '..subnet) end
        return {subnet_cd, bitlen, target, addrtype}
 end