net: ti: fix UAF in tlan_remove_one

pskrgag · davem330 · commit 0336f8ffece6 · 2021-07-09T11:01:01.000-07:00
priv is netdev private data and it cannot be used after free_netdev() call. Using priv after free_netdev() can cause UAF bug. Fix it by moving free_netdev() at the end of the function. Fixes: 1e0a8b1 ("tlan: cancel work at remove path") Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/ti/tlan.c b/drivers/net/ethernet/ti/tlan.c
@@ -313,9 +313,8 @@ static void tlan_remove_one(struct pci_dev *pdev)
 	pci_release_regions(pdev);
 #endif
 
-	free_netdev(dev);
-
 	cancel_work_sync(&priv->tlan_tqueue);
+	free_netdev(dev);
 }
 
 static void tlan_start(struct net_device *dev)

Original file line number	Diff line number	Diff line change
`@@ -313,9 +313,8 @@ static void tlan_remove_one(struct pci_dev *pdev)`
`313`	`313`	`pci_release_regions(pdev);`
`314`	`314`	`#endif`
`315`	`315`
`316`		`- free_netdev(dev);`
`317`		`-`
`318`	`316`	`cancel_work_sync(&priv->tlan_tqueue);`
	`317`	`+ free_netdev(dev);`
`319`	`318`	`}`
`320`	`319`
`321`	`320`	`static void tlan_start(struct net_device *dev)`