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

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: 0f74f8b6675c ("i3c: Make i3c_master_unregister() return void")
Cc: stable@vger.kernel.org
Signed-off-by: Kaixin Wang <kxwang23@m.fudan.edu.cn>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/stable/20240914154030.180-1-kxwang23%40m.fudan.edu.cn
Link: https://lore.kernel.org/r/20240914163932.253-1-kxwang23@m.fudan.edu.cn
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 423db3dca257b06ad05b7fbacf54704a98d8d791..a7bfc678153e6c1405a30d97678038e4e2dbf92d 100644 (file)
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/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);