This is a note to let you know that I've just added the patch titled
can: c_can_pci: c_can_pci_remove(): fix use-after-free
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
can-c_can_pci-c_can_pci_remove-fix-use-after-free.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7e20a8bd39676cf1a8e33d3c502470f78743cef5
Author: Tong Zhang <ztong0001@xxxxxxxxx>
Date: Sun Feb 28 21:45:11 2021 -0500
can: c_can_pci: c_can_pci_remove(): fix use-after-free
[ Upstream commit 0429d6d89f97ebff4f17f13f5b5069c66bde8138 ]
There is a UAF in c_can_pci_remove(). dev is released by
free_c_can_dev() and is used by pci_iounmap(pdev, priv->base) later.
To fix this issue, save the mmio address before releasing dev.
Fixes: 5b92da0443c2 ("c_can_pci: generic module for C_CAN/D_CAN on PCI")
Link: https://lore.kernel.org/r/20210301024512.539039-1-ztong0001@xxxxxxxxx
Signed-off-by: Tong Zhang <ztong0001@xxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/can/c_can/c_can_pci.c b/drivers/net/can/c_can/c_can_pci.c
index 406b4847e5dc..7efb60b50876 100644
--- a/drivers/net/can/c_can/c_can_pci.c
+++ b/drivers/net/can/c_can/c_can_pci.c
@@ -239,12 +239,13 @@ static void c_can_pci_remove(struct pci_dev *pdev)
{
struct net_device *dev = pci_get_drvdata(pdev);
struct c_can_priv *priv = netdev_priv(dev);
+ void __iomem *addr = priv->base;
unregister_c_can_dev(dev);
free_c_can_dev(dev);
- pci_iounmap(pdev, priv->base);
+ pci_iounmap(pdev, addr);
pci_disable_msi(pdev);
pci_clear_master(pdev);
pci_release_regions(pdev);
