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
}
        return System.nanoTime();
    }
    
    public void setLastAccessTime() {
        lastAccessTime = System.nanoTime();
    }
    /**
     * Set flag to signal to {@link org.elasticsearch.indices.recovery.RecoveriesCollection.RecoveryMonitor} that it must not cancel this
     * recovery temporarily. This is used by the recovery clean files step to avoid recovery failure in case a long running condition was
     * added to the shard via {@link IndexShard#addCleanFilesDependency()}.
     *
     * @return releasable that once closed will re-enable liveness checks by the recovery monitor
     */
    public Releasable disableRecoveryMonitor() {
        assert recoveryMonitorEnabled : "recovery monitor already disabled";
        recoveryMonitorEnabled = false;
        return () -> {
            setLastAccessTime();
            recoveryMonitorEnabled = true;
        };
    }
    public Store store() {
        ensureRefCount();
        return store;
    }
    /**
     * Closes the current recovery target and waits up to a certain timeout for resources to be freed.
     * Returns true if resetting the recovery was successful, false if the recovery target is already cancelled / failed or marked as done.
     */