apache/cassandra · error · MarshalException

Not enough bytes to read %dth component

Error message

Not enough bytes to read %dth component

What it means

After reading a tuple component's declared size, the buffer must contain that many bytes for the component's value. If it ends early the serialized tuple is truncated and MarshalException is thrown naming the component index.

Source

Thrown at src/java/org/apache/cassandra/cql3/CQL3Type.java:511

                if (buffer.remaining() < 4)
                    throw new MarshalException(String.format("Not enough bytes to read size of %dth component", i));

                int size = buffer.getInt();

                if (first)
                    first = false;
                else
                    target.append(", ");

                // size < 0 means null value
                if (size < 0)
                {
                    target.append("null");
                    continue;
                }

                if (buffer.remaining() < size)
                    throw new MarshalException(String.format("Not enough bytes to read %dth component", i));

                ByteBuffer field = ByteBufferUtil.readBytes(buffer, size);
                target.append(type.type(i).asCQL3Type().toCQLLiteral(field));
            }
            target.append(')');
            return target.toString();
        }

        @Override
        public final boolean equals(Object o)
        {
            if(!(o instanceof Tuple))
                return false;

            Tuple that = (Tuple)o;
            return type.equals(that.type);
        }

View on GitHub (pinned to 88fd0f6a0e)

Solutions

1. Ensure each component's serialized bytes fully follow its size prefix
2. Serialize tuples via TupleType APIs rather than manual ByteBuffer composition
3. Catch MarshalException around literal rendering of untrusted blobs

Example fix

// before
ByteBuffer b = ByteBuffer.allocate(4); b.putInt(8); // 8 declared, 0 present
String lit = tupleType.asCQL3Type().toCQLLiteral(b);
// after
ByteBuffer b = tupleType.serializer().serialize(tupleValue);
String lit = tupleType.asCQL3Type().toCQLLiteral(b);

ByteBuffer dup = buffer.duplicate();
while (dup.hasRemaining()) { int size = dup.getInt(); if (dup.remaining() < size) throw new MarshalException("component truncated"); dup.position(dup.position() + size); }

try { String lit = tupleType.asCQL3Type().toCQLLiteral(buffer); } catch (MarshalException e) { handleCorruptTuple(e); }

When it happens

Trigger: A component size prefix (e.g. 8) followed by fewer than 8 bytes; hand-built tuple buffers with wrong sizes; corrupted stored tuple blobs.

Common situations: Off-by-N errors when manually concatenating component bytes; transport truncation; attempting to render partially read data.

Related errors

• Not enough bytes to read size of %dth component
• Not enough bytes to read size of %dth field %s
• Not enough bytes to read %dth field %s
• Invalid operation (%s) for tuple column %s
• Invalid 32-bits integer value, expecting 4 bytes but got %d

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/e0fcf950a1cd167d. Report an issue: GitHub.