On Fri, Jan 03, 2025 at 03:04:20PM +0800, jianqi.ren.cn@xxxxxxxxxxxxx wrote: > From: Kaixin Wang <kxwang23@xxxxxxxxxxxxxx> > > [ Upstream commit 609366e7a06d035990df78f1562291c3bf0d4a12 ] > > In the cdns_i3c_master_probe function, &master->hj_work is bound with > cdns_i3c_master_hj. And cdns_i3c_master_interrupt can call > cnds_i3c_master_demux_ibis function to start the work. > > If we remove the module which will call cdns_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 > > | cdns_i3c_master_hj > cdns_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 cdns_i3c_master_remove. > > Signed-off-by: Kaixin Wang <kxwang23@xxxxxxxxxxxxxx> > Link: https://lore.kernel.org/r/20240911153544.848398-1-kxwang23@xxxxxxxxxxxxxx > Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> > Signed-off-by: Jianqi Ren <jianqi.ren.cn@xxxxxxxxxxxxx> > --- > drivers/i3c/master/i3c-master-cdns.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/i3c/master/i3c-master-cdns.c b/drivers/i3c/master/i3c-master-cdns.c > index b9cfda6ae9ae..4473c0b1ae2e 100644 > --- a/drivers/i3c/master/i3c-master-cdns.c > +++ b/drivers/i3c/master/i3c-master-cdns.c > @@ -1668,6 +1668,7 @@ static int cdns_i3c_master_remove(struct platform_device *pdev) > struct cdns_i3c_master *master = platform_get_drvdata(pdev); > int ret; > > + cancel_work_sync(&master->hj_work); > ret = i3c_master_unregister(&master->base); > if (ret) > return ret; > -- > 2.25.1 > > Does not apply to 6.1.y :(
