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
AtomicLong totalBytesRead = new AtomicLong();
        public InstrumentedRepo(
            RepositoryMetadata metadata,
            Environment environment,
            NamedXContentRegistry namedXContentRegistry,
            ClusterService clusterService,
            BigArrays bigArrays,
            RecoverySettings recoverySettings
        ) {
            super(metadata, environment, namedXContentRegistry, clusterService, bigArrays, recoverySettings);
        }
        @Override
        public BlobContainer shardContainer(IndexId indexId, int shardId) {
            return new FilterBlobContainer(super.shardContainer(indexId, shardId)) {
                @Override
                protected BlobContainer wrapChild(BlobContainer child) {
                    return child;
                }
                @Override
                public InputStream readBlob(String blobName) throws IOException {
                    
                    if (blobName.startsWith("__") == false) {
                        return super.readBlob(blobName);
                    }