[PATCH net] net: txgbe: fix FDIR filter leak on remove

[Chenguang Zhao <chenguang.zhao@linux.dev>]

From: Chenguang Zhao <zhaochenguang@kylinos.cn>

Perfect FDIR filters can be added while the interface is down and are
kept on the software list for later restore. unregister_netdev() only
calls ndo_stop when the device is up, so txgbe_fdir_filter_exit() in
txgbe_close() is skipped in that case and the filters are leaked on
driver remove. Free the filter list from txgbe_remove() as well.

Fixes: 4bdb441105dc ("net: txgbe: support Flow Director perfect filters")
Signed-off-by: Chenguang Zhao <zhaochenguang@kylinos.cn>
---
Reproduction:
 1. Load the driver (interface remains down after probe).
 2. Enable ntuple filters: ethtool -K <dev> ntuple on
 3. Add a perfect FDIR rule while the interface is down:
   ethtool -N <dev> flow-type ...
 4. Keep the interface down (do not bring it up).
 5. Unload the driver (rmmod / PCI unbind).
   unregister_netdev() skips ndo_stop because the device is not IFF_UP,
   and without freeing the software filter list in remove, each rule
   leaks sizeof(struct txgbe_fdir_filter).

 drivers/net/ethernet/wangxun/txgbe/txgbe_main.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
index 20c5a295c6c2..c277863baf67 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
@@ -945,6 +945,7 @@ static void txgbe_remove(struct pci_dev *pdev)
 	netdev = wx->netdev;
 	wx_disable_sriov(wx);
 	unregister_netdev(netdev);
+	txgbe_fdir_filter_exit(wx);
 
 	timer_shutdown_sync(&wx->service_timer);
 	cancel_work_sync(&wx->service_task);
-- 
2.25.1