Commit 410e610a authored Mar 18, 2023 by Zheng Wang Committed by Greg Kroah-Hartman May 30, 2023

scsi: message: mptlan: Fix use after free bug in mptlan_remove() due to race condition



[ Upstream commit f486893288f3e9b171b836f43853a6426515d800 ]

mptlan_probe() calls mpt_register_lan_device() which initializes the
&priv->post_buckets_task workqueue. A call to
mpt_lan_wake_post_buckets_task() will subsequently start the work.

During driver unload in mptlan_remove() the following race may occur:

CPU0                  CPU1

                    |mpt_lan_post_receive_buckets_work()
mptlan_remove()     |
  free_netdev()     |
    kfree(dev);     |
                    |
                    | dev->mtu
                    |   //use

Fix this by finishing the work prior to cleaning up in mptlan_remove().

[mkp: we really should remove mptlan instead of attempting to fix it]

Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Link: https://lore.kernel.org/r/20230318081635.796479-1-zyytlz.wz@163.com


Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent cc2d2b3d

drivers/message/fusion/mptlan.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1430,7 +1430,9 @@ mptlan_remove(struct pci_dev *pdev)
		{
		MPT_ADAPTER *ioc = pci_get_drvdata(pdev);
		struct net_device *dev = ioc->netdev;
		struct mpt_lan_priv *priv = netdev_priv(dev);

		cancel_delayed_work_sync(&priv->post_buckets_task);
		if(dev != NULL) {
		unregister_netdev(dev);
		free_netdev(dev);