From 95deeb29d831e2fae608439e243e7a520611e7ea Mon Sep 17 00:00:00 2001 From: Pavel Skripkin Date: Fri, 18 Jun 2021 16:49:02 +0300 Subject: [PATCH] net: ethernet: fix potential use-after-free in ec_bhf_remove [ Upstream commit 9cca0c2d70149160407bda9a9446ce0c29b6e6c6 ] static void ec_bhf_remove(struct pci_dev *dev) { ... struct ec_bhf_priv *priv = netdev_priv(net_dev); unregister_netdev(net_dev); free_netdev(net_dev); pci_iounmap(dev, priv->dma_io); pci_iounmap(dev, priv->io); ... } priv is netdev private data, but it is used after free_netdev(). It can cause use-after-free when accessing priv pointer. So, fix it by moving free_netdev() after pci_iounmap() calls. Fixes: 6af55ff52b02 ("Driver for Beckhoff CX5020 EtherCAT master module.") Signed-off-by: Pavel Skripkin Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/ec_bhf.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/ec_bhf.c b/drivers/net/ethernet/ec_bhf.c index 46b0dbab8aadc..7c992172933bc 100644 --- a/drivers/net/ethernet/ec_bhf.c +++ b/drivers/net/ethernet/ec_bhf.c @@ -576,10 +576,12 @@ static void ec_bhf_remove(struct pci_dev *dev) struct ec_bhf_priv *priv = netdev_priv(net_dev); unregister_netdev(net_dev); - free_netdev(net_dev); pci_iounmap(dev, priv->dma_io); pci_iounmap(dev, priv->io); + + free_netdev(net_dev); + pci_release_regions(dev); pci_clear_master(dev); pci_disable_device(dev);