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
maybeCheckIndex();
        recoveryState.setLocalTranslogStage();
        final RecoveryState.Translog translogRecoveryStats = recoveryState.getTranslog();
        final Engine.TranslogRecoveryRunner translogRecoveryRunner = (engine, snapshot) -> {
            translogRecoveryStats.totalOperations(snapshot.totalOperations());
            translogRecoveryStats.totalOperationsOnStart(snapshot.totalOperations());
            return runTranslogRecovery(
                engine,
                snapshot,
                Engine.Operation.Origin.LOCAL_TRANSLOG_RECOVERY,
                translogRecoveryStats::incrementRecoveredOperations
            );
        };
        loadGlobalCheckpointToReplicationTracker();
        innerOpenEngineAndTranslog(replicationTracker);
        getEngine().recoverFromTranslog(translogRecoveryRunner, Long.MAX_VALUE);
    }
    /**
     * Opens the engine on top of the existing lucene engine and translog.
     * The translog is kept but its operations won't be replayed.
     */
    public void openEngineAndSkipTranslogRecovery() throws IOException {
        assert routingEntry().recoverySource().getType() == RecoverySource.Type.PEER : "not a peer recovery [" + routingEntry() + "]";
        recoveryState.validateCurrentStage(RecoveryState.Stage.TRANSLOG);
        loadGlobalCheckpointToReplicationTracker();
        innerOpenEngineAndTranslog(replicationTracker);
        getEngine().skipTranslogRecovery();
    }
    private void innerOpenEngineAndTranslog(LongSupplier globalCheckpointSupplier) throws IOException {
        assert Thread.holdsLock(mutex) == false : "opening engine under mutex";