We saw a case where the recovery stats reported `recovered_bytes` greater than `length_in_bytes` for one file:

```
GET /_recovery?detailed

200 OK
...
{
  "name": "_buk.fdt",
  "length_in_bytes": 26891307173,
  "reused": false,
  "recovered_in_bytes": 35324928266,
  "recovered_from_snapshot_in_bytes": 8433621093
}
...
```

NB `35324928266 == 26891307173 + 8433621093`

This causes Elasticsearch to compute a negative value for the reserved space on the target node of this recovery, which prevents stats APIs from working. This appears to be caused by a network-level failure which triggers a retry without first cancelling an ongoing download of a different file with the same name from the snapshot repository.

---

### Workaround

Restart the target node to clear these stats.
server/src/main/java/org/elasticsearch/indices/recovery/MultiFileWriter.java
* Side Public License, v 1.
 */
package org.elasticsearch.indices.recovery;
import org.apache.logging.log4j.Logger;
import org.apache.lucene.store.IOContext;
import org.apache.lucene.store.IndexOutput;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.BytesRefIterator;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.bytes.BytesReference;
import org.elasticsearch.common.bytes.ReleasableBytesReference;
import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
import org.elasticsearch.core.AbstractRefCounted;
import org.elasticsearch.core.Releasable;
import org.elasticsearch.core.Releasables;
import org.elasticsearch.index.store.Store;
import org.elasticsearch.index.store.StoreFileMetadata;
import org.elasticsearch.transport.Transports;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicBoolean;
public class MultiFileWriter extends AbstractRefCounted implements Releasable {