net: davicom: fix UAF in dm9000_drv_remove

dm is netdev private data and it cannot be
used after free_netdev() call. Using dm after free_netdev()
can cause UAF bug. Fix it by moving free_netdev() at the end of the
function.

This is similar to the issue fixed in commit
ad297cd2db89 ("net: qcom/emac: fix UAF in emac_remove").

This bug is detected by our static analysis tool.

Fixes: cf9e60aa69ae ("net: davicom: Fix regulator not turned off on driver removal")
Signed-off-by: Chenyuan Yang <chenyuan0y@gmail.com>
CC: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20250123214213.623518-1-chenyuan0y@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Chenyuan Yang 2025-01-23 15:42:13 -06:00 committed by Jakub Kicinski
parent bd1bbab717
commit 19e65c45a1

View File

@ -1777,10 +1777,11 @@ static void dm9000_drv_remove(struct platform_device *pdev)
unregister_netdev(ndev);
dm9000_release_board(pdev, dm);
free_netdev(ndev); /* free device structure */
if (dm->power_supply)
regulator_disable(dm->power_supply);
free_netdev(ndev); /* free device structure */
dev_dbg(&pdev->dev, "released and freed device\n");
}