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
* {@link IllegalStateException}.
     *
     * @param opPrimaryTerm              the operation primary term
     * @param globalCheckpoint           the global checkpoint associated with the request
     * @param maxSeqNoOfUpdatesOrDeletes the max seq_no of updates (index operations overwrite Lucene) or deletes captured on the primary
     *                                   after this replication request was executed on it (see {@link #getMaxSeqNoOfUpdatesOrDeletes()}
     * @param onPermitAcquired           the listener for permit acquisition
     * @param timeout                    the maximum time to wait for the in-flight operations block
     */
    public void acquireAllReplicaOperationsPermits(
        final long opPrimaryTerm,
        final long globalCheckpoint,
        final long maxSeqNoOfUpdatesOrDeletes,
        final ActionListener<Releasable> onPermitAcquired,
        final TimeValue timeout
    ) {
        innerAcquireReplicaOperationPermit(
            opPrimaryTerm,
            globalCheckpoint,
            maxSeqNoOfUpdatesOrDeletes,
            onPermitAcquired,
            true,
            listener -> asyncBlockOperations(listener, timeout.duration(), timeout.timeUnit())
        );
    }
    private void innerAcquireReplicaOperationPermit(
        final long opPrimaryTerm,
        final long globalCheckpoint,
        final long maxSeqNoOfUpdatesOrDeletes,
        final ActionListener<Releasable> onPermitAcquired,