|WARNING| net/iavf: fix memory leaks in RSS flow engine

[dpdklab at iol.unh.edu]

Test-Label: ai-code-review
Test-Status: WARNING
https://dpdk.org/patch/170997

_AI Code Review_

=== Patch Review: series.patch (via Claude) ===
Review date: 2026-10-10

# DPDK Patch Review

## Errors

**Error 1: Early return does not clean up rss_cfg**

**File:** `drivers/net/intel/iavf/iavf_hash.c`  
**Function:** `iavf_hash_destroy()`  
**Line:** ~1648 (after changes)

```c
if (ret) {
    PMD_DRV_LOG(ERR, "fail to del RSS configure");
    rte_flow_error_set(error, -ret,
               RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
               "Failed to delete rss rule.");
    return -rte_errno;
}
```

The error path after `iavf_add_del_rss_cfg()` fails now returns early without freeing `rss_cfg` or clearing `flow->rule`. The patch correctly moved the `rte_free(rss_cfg)` and `flow->rule = NULL` outside the `!vf->vf_reset` conditional, but the early return on error bypasses them, leaking the config.

**Suggested fix:**

```c
if (!vf->vf_reset) {
    ret = iavf_add_del_rss_cfg(ad, rss_cfg, false);
    if (ret) {
        PMD_DRV_LOG(ERR, "fail to del RSS configure");
        rte_flow_error_set(error, -ret,
                   RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
                   "Failed to delete rss rule.");
        ret = -rte_errno;
    }
}

flow->rule = NULL;
rte_free(rss_cfg);

return ret;
```

---

## Warnings

None.

---

## Info

**Info 1: Pre-existing NULL check defensive pattern**

**File:** `drivers/net/intel/iavf/iavf_hash.c`  
**Function:** `iavf_hash_destroy()`  
**Context:** The function unconditionally dereferences `flow->rule` without checking if it is NULL.

This is pre-existing code not introduced by this patch. If `flow->rule` is NULL when `iavf_hash_destroy()` is called, the assignment `rss_cfg = (struct virtchnl_rss_cfg *)flow->rule;` followed by `rte_free(rss_cfg);` will free NULL (which is safe), but the function should handle this defensively or document that callers guarantee `flow->rule` is non-NULL.

Not introduced by this patch.

---

Review-Result: ERROR