i3c: master: svc: Fix use after free vulnerability in svc_i3c_master Driver Due to Race Condition

In the svc_i3c_master_probe function, &master->hj_work is bound with
svc_i3c_master_hj_work, &master->ibi_work is bound with
svc_i3c_master_ibi_work. And svc_i3c_master_ibi_work  can start the
hj_work, svc_i3c_master_irq_handler can start the ibi_work.

If we remove the module which will call svc_i3c_master_remove to
make cleanup, it will free master->base through i3c_master_unregister
while the work mentioned above will be used. The sequence of operations
that may lead to a UAF bug is as follows:

CPU0                                         CPU1

                                    | svc_i3c_master_hj_work
svc_i3c_master_remove               |
i3c_master_unregister(&master->base)|
device_unregister(&master->dev)     |
device_release                      |
//free master->base                 |
                                    | i3c_master_do_daa(&master->base)
                                    | //use master->base

Fix it by ensuring that the work is canceled before proceeding with the
cleanup in svc_i3c_master_remove.

Fixes: 0f74f8b ("i3c: Make i3c_master_unregister() return void")
Cc: [email protected]
Signed-off-by: Kaixin Wang <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Reviewed-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/stable/20240914154030.180-1-kxwang23%40m.fudan.edu.cn
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

Author: Kaixin Wang

drivers/i3c/master/svc-i3c-master.c

@@ -1840,6 +1840,7 @@ static void svc_i3c_master_remove(struct platform_device *pdev)
 {
 	struct svc_i3c_master *master = platform_get_drvdata(pdev);
 
+	cancel_work_sync(&master->hj_work);
 	i3c_master_unregister(&master->base);
 
 	pm_runtime_dont_use_autosuspend(&pdev->dev);