On Mon, May 13, 2024 at 10:19:48AM +0800, Sicong Huang wrote: > This bug exists in drivers/usb/cdns3/cdns3-gadget.c. Function > __cdns3_gadget_init will call cdns3_gadget_start to do futher jobs > during the initialization proccess of cdns3 gadget. In cdns3_gadget_start, > &priv_dev->pending_status_wq is bound with cdns3_pending_setup_status_handler. > Then this work will be added to system_freezable_wq in cdns3_gadget_ep0_queue. > Here is the code. > queue_work(system_freezable_wq, &priv_dev->pending_status_wq); > > If we call cdns3_gadget_exit to remove the device and make cleanup, > there are some unfinished works. This function will call cdns3_free_all_eps to > free all the endpoints. However, if cdns3_pending_setup_status_handler is > scheduled to run after the free job, it will cause use-after-free error as > cdns3_pending_setup_status_handler will use the endpoint in the following code. > request->complete(&priv_dev->eps[0]->endpoint, request); > > The possible execution flow that may lead to this issue is as follows: > CPU0 CPU1 > | __cdns3_gadget_init > | cdns3_gadget_start > cdns3_gadget_exit | > cdns3_free_all_eps | > devm_kfree (free) | > | cdns3_pending_setup_status_handler > | &priv_dev->eps[0]->endpoint (use) > > Fix it by cleaning the work in cdns3_gadget_exit. > > Signed-off-by: Sicong Huang <congei42@xxxxxxx> > --- > drivers/usb/cdns3/cdns3-gadget.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c > index fd1beb10bba7..0f2e143bd17a 100644 > --- a/drivers/usb/cdns3/cdns3-gadget.c > +++ b/drivers/usb/cdns3/cdns3-gadget.c > @@ -3252,6 +3252,9 @@ static void cdns3_gadget_exit(struct cdns *cdns) > pm_runtime_mark_last_busy(cdns->dev); > pm_runtime_put_autosuspend(cdns->dev); > > + cancel_work_sync(&priv_dev->pending_status_wq); > + cancel_work_sync(&priv_dev->aligned_buf_wq); > + > usb_del_gadget(&priv_dev->gadget); > devm_free_irq(cdns->dev, cdns->dev_irq, priv_dev); > > -- > 2.34.1 What commit id does this fix? thanks, greg k-h
