[PATCH] net: pxa168_eth: Fix a potential data race in pxa168_eth_remove

Pavel Andrianov
2021-03-10T08:21:33Z

pxa168_eth_remove() firstly calls unregister_netdev(),
then cancels a timeout work. unregister_netdev() shuts down a device
interface and removes it from the kernel tables. If the timeout occurs
in parallel, the timeout work (pxa168_eth_tx_timeout_task) performs stop
and open of the device. It may lead to an inconsistent state and memory
leaks.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Pavel Andrianov <andrianov@ispras.ru>
---
drivers/net/ethernet/marvell/pxa168_eth.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/pxa168_eth.c b/drivers/net/ethernet/marvell/pxa168_eth.c
index d1e4d42e497d..3712e1786091 100644
--- a/drivers/net/ethernet/marvell/pxa168_eth.c
+++ b/drivers/net/ethernet/marvell/pxa168_eth.c
@@ -1544,8 +1544,8 @@ static int pxa168_eth_remove(struct platform_device *pdev)
clk_disable_unprepare(pep->clk);
mdiobus_unregister(pep->smi_bus);
mdiobus_free(pep->smi_bus);
- unregister_netdev(dev);
cancel_work_sync(&pep->tx_timeout_task);
+ unregister_netdev(dev);
free_netdev(dev);
return 0;
}
--
2.25.1