[PATCH 4.4 14/47] net: ti: fix UAF in tlan_remove_one

Greg Kroah-Hartman
2021-07-26T15:40:52Z

From: Pavel Skripkin <paskripkin@gmail.com>

commit 0336f8ffece62f882ab3012820965a786a983f70 upstream.

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: 1e0a8b13d355 ("tlan: cancel work at remove path")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/ti/tlan.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- 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_d
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)