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
preIndex.seqNo(),
                    routingEntry().allocationId(),
                    preIndex.primaryTerm(),
                    getOperationPrimaryTerm(),
                    preIndex.origin(),
                    result.getSeqNo(),
                    result.getTerm(),
                    result.getFailure()
                );
            }
        } catch (Exception e) {
            if (logger.isTraceEnabled()) {
                logger.trace(
                    () -> format(
                        "index-fail [%s] seq# [%s] allocation-id [%s] primaryTerm [%s] operationPrimaryTerm [%s] origin [%s]",
                        preIndex.id(),
                        preIndex.seqNo(),
                        routingEntry().allocationId(),
                        preIndex.primaryTerm(),
                        getOperationPrimaryTerm(),
                        preIndex.origin()
                    ),
                    e
                );
            }
            indexingOperationListeners.postIndex(shardId, preIndex, e);
            throw e;
        }
        indexingOperationListeners.postIndex(shardId, preIndex, result);
        return result;