pkg/record: Decode should return ErrUnexpectedEOF instead of EOF when header is read but expected data is missing

[dolmen]

When a record header is correctly read, but no data follows (io.ReadFull line 86 returns io.EOF), Decode will return io.EOF instead of io.ErrUnexpectedEOF (which would signal a partial broken record instead of no record).

sshproxy/pkg/record/record.go

Lines 63 to 91 in 7239859

	// Decode reads a binary record from an io.Reader and fills the provided
	// *Record struct.
	//
	// It uses a pointer over a *Record struct instead of returning a *Record
	// struct for performance reason: it tries to reuse the already allocated Data
	// field.
	func Decode(rd io.Reader, rec *Record) error {
	var hdr Header
	if err := binary.Read(rd, binary.BigEndian, &hdr); err != nil {
	return err
	}
	rec.Time = time.Unix(0, int64(hdr.Time))
	rec.Fd = int(hdr.Fd)
	rec.Size = int(hdr.Size)
	// Reuse the data slice
	if cap(rec.Data) >= int(rec.Size) {
	rec.Data = rec.Data[:rec.Size]
	} else {
	rec.Data = make([]byte, rec.Size)
	}
	if _, err := io.ReadFull(rd, rec.Data); err != nil {
	return err
	}
	return nil
	}

io.ErrUnexpectedEOF would signal a problem with the file instead of just hiding the issue to the caller.