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/snapshot-based-recoveries/src/internalClusterTest/java/org/elasticsearch/xpack/snapshotbasedrecoveries/recovery/SnapshotBasedIndexRecoveryIT.java
AtomicBoolean delayRecoveryExceptionSent = new AtomicBoolean();
                sourceMockTransportService.addRequestHandlingBehavior(
                    PeerRecoverySourceService.Actions.START_RECOVERY,
                    (handler, request, channel, task) -> {
                        if (delayRecoveryExceptionSent.compareAndSet(false, true)) {
                            channel.sendResponse(new DelayRecoveryException("delay"));
                        } else {
                            startRecoveryRetryReceived.countDown();
                            handler.messageReceived(request, channel, task);
                        }
                    }
                );
                String indexRecoveredFromSnapshot1 = indices.get(0);
                assertAcked(
                    client().admin()
                        .indices()
                        .prepareUpdateSettings(indexRecoveredFromSnapshot1)
                        .setSettings(Settings.builder().put("index.routing.allocation.require._name", targetNode))
                        .get()
                );
                startRecoveryRetryReceived.await();
                sourceMockTransportService.clearAllRules();
                awaitForRecoverSnapshotFileRequestReceived.run();
                String indexRecoveredFromPeer = indices.get(1);
                assertAcked(
                    client().admin()
                        .indices()
                        .prepareUpdateSettings(indexRecoveredFromPeer)
                        .setSettings(Settings.builder().put("index.routing.allocation.require._name", targetNode))
                        .get()