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
acquirePrimaryOperationPermit(onPermitAcquired, executorOnDelay, debugInfo, false);
    }
    public void acquirePrimaryOperationPermit(
        ActionListener<Releasable> onPermitAcquired,
        String executorOnDelay,
        Object debugInfo,
        boolean forceExecution
    ) {
        verifyNotClosed();
        assert shardRouting.primary() : "acquirePrimaryOperationPermit should only be called on primary shard: " + shardRouting;
        indexShardOperationPermits.acquire(
            wrapPrimaryOperationPermitListener(onPermitAcquired),
            executorOnDelay,
            forceExecution,
            debugInfo
        );
    }
    /**
     * Acquire all primary operation permits. Once all permits are acquired, the provided ActionListener is called.
     * It is the responsibility of the caller to close the {@link Releasable}.
     */
    public void acquireAllPrimaryOperationsPermits(final ActionListener<Releasable> onPermitAcquired, final TimeValue timeout) {
        verifyNotClosed();
        assert shardRouting.primary() : "acquireAllPrimaryOperationsPermits should only be called on primary shard: " + shardRouting;
        asyncBlockOperations(wrapPrimaryOperationPermitListener(onPermitAcquired), timeout.duration(), timeout.timeUnit());
    }
    /**
     * Wraps the action to run on a primary after acquiring permit. This wrapping is used to check if the shard is in primary mode before
     * executing the action.
     *