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.
x-pack/plugin/searchable-snapshots/src/main/java/org/elasticsearch/xpack/searchablesnapshots/recovery/SearchableSnapshotRecoveryState.java
private boolean preWarmComplete;
    private boolean remoteTranslogSet;
    public SearchableSnapshotRecoveryState(ShardRouting shardRouting, DiscoveryNode targetNode, @Nullable DiscoveryNode sourceNode) {
        super(shardRouting, targetNode, sourceNode, new Index());
    }
    @Override
    public synchronized RecoveryState setStage(Stage stage) {
        
        if (getStage() == Stage.DONE || stage == Stage.FINALIZE && remoteTranslogSet) {
            return this;
        }
        
        
        if (preWarmComplete == false && stage == Stage.DONE) {
            validateCurrentStage(Stage.FINALIZE);
            return this;
        }
        if (stage == Stage.INIT) {
            remoteTranslogSet = false;