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/RecoveryTarget.java
@Nullable
    public ActionListener<Void> markRequestReceivedAndCreateListener(long requestSeqNo, ActionListener<Void> listener) {
        return requestTracker.markReceivedAndCreateListener(requestSeqNo, listener);
    }
    public long recoveryId() {
        return recoveryId;
    }
    public ShardId shardId() {
        return shardId;
    }
    public IndexShard indexShard() {
        ensureRefCount();
        return indexShard;
    }
    public DiscoveryNode sourceNode() {
        return this.sourceNode;
    }
    public RecoveryState state() {
        return indexShard.recoveryState();
    }
    public CancellableThreads cancellableThreads() {
        return cancellableThreads;
    }
    public boolean hasPermitToDownloadSnapshotFiles() {
        return snapshotFileDownloadsPermit != null;
    }
    
    public long lastAccessTime() {
        if (recoveryMonitorEnabled) {
            return lastAccessTime;