aeron-io/aeron · error · InvalidMessage

Invalid value length

Error message

Invalid value length

What it means

parseNumber in CborDecode requires the CBOR additional-info bits to encode either an inline value or 1, 2, 4, or 8 following bytes. Any other additional-content value (the reserved/invalid lengths like 7 for integer major types, or >7 non-standard) hits the else branch and throws. The number is otherwise read big-endian and negated for negative-integer major type.

Solutions

1. Ensure the CBOR payload encodes integers with additional-info 24/25/26/27 (1/2/4/8 bytes) or inline (<24).
2. Re-capture the event log with matching encoder/decoder versions.
3. Validate the buffer offset alignment before parseNumber runs.
4. Patch parseNumber to accept additional encodings if your encoder emits them.

Example fix

// before
else
{
    throw new InvalidMessage("Invalid value length");
}
// after
else
{
    throw new InvalidMessage("Invalid CBOR integer additional-info value=" + valueAdditionalContent);
}

// verify additional-info bits of the number header are a supported width
final int extraInfo = buffer.getByte(offset) & 0b000_11111;
if (extraInfo > 27 || (extraInfo >= 7 && extraInfo <= 23)) { /* unsupported width */ }

boolean isSupportedCborIntegerEncoding(final byte headerByte)
{
    final int info = headerByte & 0b000_11111;
    return info < 24 || info == 24 || info == 25 || info == 26 || info == 27;
}

try
{
    value = CborDecode.parseLong(state);
}
catch (final InvalidMessage ex)
{
    LOGGER.warn("bad integer encoding at offset " + state.offset());
    return false;
}

When it happens

Trigger: CBOR integer whose additional-info byte is not 0-7-compatible with the supported widths — e.g. value 7 (float/simple encoding) on a 0/1 major type, or a corrupt length byte in the log buffer.

Common situations: Decoding logs produced by non-standard CBOR encoders; corrupted capture buffers; hand-crafted CBOR in tests; decoder pointed at wrong offset so a float header is read as an integer.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

• Invalid value type
• Invalid key length
• Terminated prematurely
• Expected timestamp
• Expected boolean

AI-assisted analysis of aeron-io/aeron@6d60124e15 (2026-09-12). Data as JSON: /api/errors/b8ac20051516912e. Report an issue: GitHub.

Appendix: source

Thrown at aeron-client/src/main/java/io/aeron/logging/CborDecode.java:307

            state.ensureRemaining(2);
            value = 0xFFFF & state.buffer().getShort(state.offset(), BIG_ENDIAN);
            state.incrementOffset(2);
        }
        else if (ADDITIONAL_CONTENT_4_BYTE == valueAdditionalContent)
        {
            state.ensureRemaining(4);
            value = 0xFFFFFFFFL & state.buffer().getInt(state.offset(), BIG_ENDIAN);
            state.incrementOffset(4);
        }
        else if (ADDITIONAL_CONTENT_8_BYTE == valueAdditionalContent)
        {
            state.ensureRemaining(8);
            value = state.buffer().getLong(state.offset(), BIG_ENDIAN);
            state.incrementOffset(8);
        }
        else
        {
            throw new InvalidMessage("Invalid value length");
        }

        if (NEGATIVE_INTEGER_MAJOR_TYPE == valueMajorType)
        {
            value = ~value;
        }

        return value;
    }

    private void parseByteArray(
        final DecodingState state,
        final DirectBuffer targetBuffer,
        final int keyAdditionalContent)
    {
        if (keyAdditionalContent < ADDITIONAL_CONTENT_1_BYTE)
        {
            targetBuffer.wrap(state.buffer(), state.offset(), keyAdditionalContent);

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