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
synchronized (engineMutex) {
                        if (newEngineReference.get() == null) {
                            throw new AlreadyClosedException("engine was closed");
                        }
                        return newEngineReference.get().acquireSafeIndexCommit();
                    }
                }
                @Override
                public void close() throws IOException {
                    assert Thread.holdsLock(engineMutex);
                    Engine newEngine = newEngineReference.get();
                    if (newEngine == currentEngineReference.get()) {
                        
                        newEngine = null;
                    }
                    IOUtils.close(super::close, newEngine);
                }
            };
            IOUtils.close(currentEngineReference.getAndSet(readOnlyEngine));
            newEngineReference.set(engineFactory.newReadWriteEngine(newEngineConfig(replicationTracker)));
            onNewEngine(newEngineReference.get());
        }
        final Engine.TranslogRecoveryRunner translogRunner = (engine, snapshot) -> runTranslogRecovery(
            engine,
            snapshot,
            Engine.Operation.Origin.LOCAL_RESET,
            () -> {
                
            }
        );