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") Signed-off-by: Kaixin Wang kxwang23@m.fudan.edu.cn Reviewed-by: Miquel Raynal miquel.raynal@bootlin.com
--- v2: - add fixes tag and cc stable, suggested by Frank - add Reviewed-by label from Miquel - Link to v1: https://lore.kernel.org/r/20240911150135.839946-1-kxwang23@m.fudan.edu.cn --- drivers/i3c/master/svc-i3c-master.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c index 0a68fd1b81d4..e084ba648b4a 100644 --- a/drivers/i3c/master/svc-i3c-master.c +++ b/drivers/i3c/master/svc-i3c-master.c @@ -1775,6 +1775,7 @@ 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);