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
store.directory().sync(Collections.singleton(tempFileName));
        } catch (Exception e) {
            tempFileNames.remove(tempFileName);
            store.deleteQuiet(tempFileName);
            indexState.resetRecoveredBytesOfFile(fileName);
            throw e;
        } finally {
            decRef();
        }
    }
    public void deleteTempFiles() {
        incRef();
        try {
            for (String tempFileName : tempFileNames.keySet()) {
                store.deleteQuiet(tempFileName);
            }
            tempFileNames.clear();
        } finally {
            decRef();
        }
    }
    
    String getTempNameForFile(String origFile) {
        return tempFilePrefix + origFile;
    }
    public IndexOutput getOpenIndexOutput(String key) {
        ensureOpen.run();
        return openIndexOutputs.get(key);
    }