prestodb/presto · warning · PrestoException

GENERIC_INTERNAL_ERROR

GENERIC_INTERNAL_ERROR

Error message

Invalid InetAddress length: ${addressLength}

What it means

Internal ip_prefix construction validates the raw InetAddress length (4 for IPv4, 16 for IPv6) before applying subnet bounds. Any other length indicates an unexpected address representation, so Presto throws GENERIC_INTERNAL_ERROR. This should be unreachable via normal SQL input and usually indicates a bug or corrupted IPPREFIX/VARCHAR data.

Source

Thrown at presto-main-base/src/main/java/com/facebook/presto/operator/scalar/IpPrefixFunctions.java:136

    }

    private IpPrefixFunctions() {}

    @Description("IP prefix for a given IP address and subnet size")
    @ScalarFunction("ip_prefix")
    @SqlType(StandardTypes.IPPREFIX)
    public static Slice ipPrefix(@SqlType(StandardTypes.IPADDRESS) Slice value, @SqlType(StandardTypes.BIGINT) long subnetSize)
    {
        InetAddress address = toInetAddress(value);
        int addressLength = address.getAddress().length;
        if (addressLength == 4) {
            checkCondition(0 <= subnetSize && subnetSize <= 32, INVALID_FUNCTION_ARGUMENT, "IPv4 subnet size must be in range [0, 32]");
        }
        else if (addressLength == 16) {
            checkCondition(0 <= subnetSize && subnetSize <= 128, INVALID_FUNCTION_ARGUMENT, "IPv6 subnet size must be in range [0, 128]");
        }
        else {
            throw new PrestoException(GENERIC_INTERNAL_ERROR, "Invalid InetAddress length: " + addressLength);
        }

        return castFromVarcharToIpPrefix(utf8Slice(InetAddresses.toAddrString(address) + "/" + subnetSize));
    }

    @Description("IP prefix for a given IP address and subnet size")
    @ScalarFunction("ip_prefix")
    @LiteralParameters("x")
    @SqlType(StandardTypes.IPPREFIX)
    public static Slice stringIpPrefix(@SqlType("varchar(x)") Slice slice, @SqlType(StandardTypes.BIGINT) long subnetSize)
    {
        return ipPrefix(castFromVarcharToIpAddress(slice), subnetSize);
    }

    @Description("Smallest IP address for a given IP prefix")
    @ScalarFunction("ip_subnet_min")
    @SqlType(StandardTypes.IPADDRESS)
    public static Slice ipSubnetMin(@SqlType(StandardTypes.IPPREFIX) Slice value)

View on GitHub (pinned to 55bb57d202)

Solutions

  1. Verify the address string passed to ip_prefix() is a well-formed IPv4 or IPv6 literal.
  2. If inputs come from a UDF/connector, check that it returns standard IP strings.
  3. Report as a bug with the offending input if a normal IP string triggers it.

Example fix

// before
SELECT ip_prefix(address_col, 24) -- address_col contains non-standard bytes
// after
SELECT ip_prefix(CAST(address_col AS VARCHAR), 24) -- with validated IP strings
Defensive patterns

Strategy: validation

Validate before calling

-- ensure the input parses to a normal IPv4/IPv6 address first
SELECT ip_prefix(CAST(address AS VARCHAR), 24) FROM t WHERE address LIKE '%.%' OR address LIKE '%:%'

Try / catch

// client
try {
    executeQuery("SELECT ip_prefix(addr, 24) FROM t");
} catch (QueryFailedException e) {
    // GENERIC_INTERNAL_ERROR here indicates a decoder bug; report with the input
}

Prevention

When it happens

Trigger: Calling ip_prefix(varchar, integer) where the parsed InetAddress has a byte length other than 4 or 16 — only possible through an internal/decoder bug or corrupted input, since normal parse paths yield only IPv4/IPv6 addresses.

Common situations: Custom address parsing extensions feeding malformed bytes; engine bugs in InetAddress decoding; upstream data corruption reaching an unexpected code path.

Related errors

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/066303dc48180a6a. Report an issue: GitHub.