lutzroeder/netron · error · Error

Expected ${this._position - this._length} more bytes. The fi

Error message

Expected ${this._position - this._length} more bytes. The file might be corrupted. Unexpected end of file.

What it means

Thrown by the memory-backed stream's seek() when the requested position is beyond the end of the buffer or negative (negative positions are interpreted relative to the end, so only out-of-range values throw). It signals that a model parser attempted to jump past the data available, typically because internal offsets in the file are inconsistent with its actual size.

Source

Thrown at source/node.js:33

    get position() {
        return this._position;
    }

    get length() {
        return this._length;
    }

    stream(length) {
        const stream = new node.FileStream(this._file, this._start + this._position, length, this._mtime);
        this.skip(length);
        return stream;
    }

    seek(position) {
        this._position = position >= 0 ? position : this._length + position;
        if (this._position > this._length || this._position < 0) {
            throw new Error(`Expected ${this._position - this._length} more bytes. The file might be corrupted. Unexpected end of file.`);
        }
    }

    skip(offset) {
        this._position += offset;
        if (this._position > this._length || this._position < 0) {
            throw new Error(`Expected ${this._position - this._length} more bytes. The file might be corrupted. Unexpected end of file.`);
        }
    }

    peek(length) {
        length = length === undefined ? this._length - this._position : length;
        if (length < 0x10000000) {
            const position = this._fill(length);
            this._position -= length;
            return this._buffer.subarray(position, position + length);
        }
        const position = this._position;

View on GitHub (pinned to d8a543f5f8)

Solutions

Verify the file size and integrity (re-download or re-export the model).
Check the parser logic that computed the position — a stored offset/length field read with the wrong endianness or type can yield huge values.
Wrap seek() calls in try-catch to convert this into a user-facing 'corrupted file' message.

Example fix

// before
stream.seek(offsetFromHeader);

// after
if (offsetFromHeader < 0 || offsetFromHeader > stream.length) {
    throw new Error(`Header offset ${offsetFromHeader} out of range for file of ${stream.length} bytes`);
}
stream.seek(offsetFromHeader);

Defensive patterns

Strategy: validation

Validate before calling

function safeSeek(stream, position) {
    const abs = position >= 0 ? position : stream.length + position;
    if (abs < 0 || abs > stream.length) {
        throw new Error(`seek(${position}) out of range for ${stream.length} bytes`);
    }
    stream.seek(position);
}

Try / catch

try { stream.seek(pos); } catch (e) { if (/more bytes/.test(e.message)) throw new Error('Model file appears truncated'); throw e; }

Prevention

Validate stored offsets against file size before seeking.
Checksum model files after download/export.
Remember negative positions are relative to end-of-stream in this API.

When it happens

Trigger: Calling seek(position) with position > stream length or a negative position whose absolute value exceeds length; commonly triggered by model-format code following a stored offset field into a truncated file.

Common situations: Truncated or corrupted model files (interrupted download/export), files where a length-prefixed section claims more data than present, or passing a negative seek offset when the intent was relative skipping.

Related errors

AI-assisted analysis of lutzroeder/netron@d8a543f5f8 (2026-08-27). Data as JSON: /api/errors/ee56cbe2ac006bea. Report an issue: GitHub.