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/index/shard/IndexShard.java
listener.onFailure(
                            new IndexShardClosedException(shardId(), "timed out waiting for relocation hand-off to complete")
                        );
                    } else {
                        listener.onFailure(e);
                    }
                }
            }, 30L, TimeUnit.MINUTES, ThreadPool.Names.SAME); 
                                                              
        }
    }
    private void verifyRelocatingState() {
        if (state != IndexShardState.STARTED) {
            throw new IndexShardNotStartedException(shardId, state);
        }
        /*
         * If the master cancelled recovery, the target will be removed and the recovery will be cancelled. However, it is still possible
         * that we concurrently end up here and therefore have to protect that we do not mark the shard as relocated when its shard routing
         * says otherwise.
         */
        if (shardRouting.relocating() == false) {
            throw new IllegalIndexShardStateException(shardId, IndexShardState.STARTED, ": shard is no longer relocating " + shardRouting);
        }
        if (primaryReplicaResyncInProgress.get()) {
            throw new IllegalIndexShardStateException(
                shardId,
                IndexShardState.STARTED,
                ": primary relocation is forbidden while primary-replica resync is in progress " + shardRouting
            );
        }