In the Linux kernel, the following vulnerability has been resolved:

ntb: ntb_hw_switchtec: Fix use after free vulnerability in switchtec_ntb_remove due to race condition

In the switchtec_ntb_add function, it can call switchtec_ntb_init_sndev
function, then &sndev->check_link_status_work is bound with
check_link_status_work. switchtec_ntb_link_notification may be called
to start the work.

If we remove the module which will call switchtec_ntb_remove to make
cleanup, it will free sndev through kfree(sndev), while the work
mentioned above will be used. The sequence of operations that may lead
to a UAF bug is as follows:

CPU0                                 CPU1

                        | check_link_status_work
switchtec_ntb_remove    |
kfree(sndev);           |
                        | if (sndev->link_force_down)
                        | // use sndev

Fix it by ensuring that the work is canceled before proceeding with
the cleanup in switchtec_ntb_remove.

kernel.org https://git.kernel.org/stable/c/177925d9c8715a897bb79eca62628862213ba956 [No types assigned]

kernel.org https://git.kernel.org/stable/c/3ae45be8492460a35b5aebf6acac1f1d32708946 [No types assigned]

kernel.org https://git.kernel.org/stable/c/92728fceefdaa2a0a3aae675f86193b006eeaa43 [No types assigned]

kernel.org https://git.kernel.org/stable/c/b650189687822b705711f0567a65a164a314d8df [No types assigned]

kernel.org https://git.kernel.org/stable/c/e51aded92d42784313ba16c12f4f88cc4f973bbb [No types assigned]

kernel.org https://git.kernel.org/stable/c/fa840ba4bd9f3bad7f104e5b32028ee73af8b3dd [No types assigned]