ethernet: ucc_geth: fix use-after-free in ucc_geth_remove()

ugeth is the netdiv_priv() part of the netdevice. Accessing the memory
pointed to by ugeth (such as done by ucc_geth_memclean() and the two
of_node_puts) after free_netdev() is thus use-after-free.

Fixes: 80a9fad8e89a ("ucc_geth: fix module removal")
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/freescale/ucc_geth.c b/drivers/net/ethernet/freescale/ucc_geth.c
index d6dbae4..6d853f0 100644 (file)
--- a/drivers/net/ethernet/freescale/ucc_geth.c
+++ b/drivers/net/ethernet/freescale/ucc_geth.c
@@ -3935,12 +3935,12 @@ static int ucc_geth_remove(struct platform_device* ofdev)
        struct device_node *np = ofdev->dev.of_node;
 
        unregister_netdev(dev);
-       free_netdev(dev);
        ucc_geth_memclean(ugeth);
        if (of_phy_is_fixed_link(np))
                of_phy_deregister_fixed_link(np);
        of_node_put(ugeth->ug_info->tbi_node);
        of_node_put(ugeth->ug_info->phy_node);
+       free_netdev(dev);
 
        return 0;
 }