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
runnable.run();
        } else {
            synchronized (afterCleanFilesActions) {
                afterCleanFilesActions.add(runnable);
            }
            if (outstandingCleanFilesConditions.get() == 0) {
                runAfterCleanFilesActions();
            }
        }
    }
    
    public int outstandingCleanFilesConditions() {
        return outstandingCleanFilesConditions.get();
    }
    private void runAfterCleanFilesActions() {
        synchronized (afterCleanFilesActions) {
            final Executor executor = threadPool.generic();
            Runnable afterCleanFilesAction;
            while ((afterCleanFilesAction = afterCleanFilesActions.poll()) != null) {
                executor.execute(afterCleanFilesAction);
            }
        }
    }
    /**
     * Updates the known allocation IDs and the local checkpoints for the corresponding allocations from a primary relocation source.
     *
     * @param primaryContext the sequence number context
     */
    public void activateWithPrimaryContext(final ReplicationTracker.PrimaryContext primaryContext) {
        assert shardRouting.primary() && shardRouting.isRelocationTarget()