golang/go · error

zip: invalid comment length

Error message

zip: invalid comment length

What it means

Error "zip: invalid comment length" thrown in golang/go.

Source

Thrown at src/archive/zip/reader.go:579

		if i == 1 || bLen == size {
			return nil, 0, ErrFormat
		}
	}

	// read header into struct
	b := readBuf(buf[4:]) // skip signature
	d := &directoryEnd{
		diskNbr:            uint32(b.uint16()),
		dirDiskNbr:         uint32(b.uint16()),
		dirRecordsThisDisk: uint64(b.uint16()),
		directoryRecords:   uint64(b.uint16()),
		directorySize:      uint64(b.uint32()),
		directoryOffset:    uint64(b.uint32()),
		commentLen:         b.uint16(),
	}
	l := int(d.commentLen)
	if l > len(b) {
		return nil, 0, errors.New("zip: invalid comment length")
	}
	d.comment = string(b[:l])

	// These values mean that the file can be a zip64 file
	if d.directoryRecords == 0xffff || d.directorySize == 0xffffffff || d.directoryOffset == 0xffffffff {
		p, err := findDirectory64End(r, directoryEndOffset)
		if err == nil && p >= 0 {
			directoryEndOffset = p
			err = readDirectory64End(r, p, d)
		}
		if err != nil {
			return nil, 0, err
		}
	}

	maxInt64 := uint64(1<<63 - 1)
	if d.directorySize > maxInt64 || d.directoryOffset > maxInt64 {
		return nil, 0, ErrFormat

View on GitHub (pinned to b6b368adc5)

When it happens

Trigger: Thrown at src/archive/zip/reader.go:579 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of golang/go@b6b368adc5 (2026-08-12). Data as JSON: /api/errors/a6541def0dc8a7e8. Report an issue: GitHub.