Messages in this thread | | | From | John Stultz <> | Date | Mon, 13 Mar 2023 12:57:44 -0700 | Subject | Re: [PATCH] misc: hisi_hikey_usb: Fix use after free bug in hisi_hikey_usb_remove due to race condition |
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On Sun, Mar 12, 2023 at 7:53 AM Zheng Wang <zyytlz.wz@163.com> wrote: > > In hisi_hikey_usb_probe, it called hisi_hikey_usb_of_role_switch > and bound &hisi_hikey_usb->work with relay_set_role_switch. > When it calls hub_usb_role_switch_set, it will finally call > schedule_work to start the work. > > When we call hisi_hikey_usb_remove to remove the driver, there > may be a sequence as follows: > > Fix it by finishing the work before cleanup in hisi_hikey_usb_remove. > > CPU0 CPU1 > > |relay_set_role_switch > hisi_hikey_usb_remove| > usb_role_switch_put| > usb_role_switch_release | > kfree(sw) | > | usb_role_switch_set_role > | //use > > Fixes: 7a6ff4c4cbc3 ("misc: hisi_hikey_usb: Driver to support onboard USB gpio hub on Hikey960") > Signed-off-by: Zheng Wang <zyytlz.wz@163.com> > --- > drivers/misc/hisi_hikey_usb.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/misc/hisi_hikey_usb.c b/drivers/misc/hisi_hikey_usb.c > index 2165ec35a343..26fc895c4418 100644 > --- a/drivers/misc/hisi_hikey_usb.c > +++ b/drivers/misc/hisi_hikey_usb.c > @@ -242,6 +242,7 @@ static int hisi_hikey_usb_probe(struct platform_device *pdev) > static int hisi_hikey_usb_remove(struct platform_device *pdev) > { > struct hisi_hikey_usb *hisi_hikey_usb = platform_get_drvdata(pdev); > + cancel_work_sync(&hisi_hikey_usb->work); > > if (hisi_hikey_usb->hub_role_sw) { > usb_role_switch_unregister(hisi_hikey_usb->hub_role_sw);
Looks sane to me. Pulling in Sumit and YongQin as they have hardware and can test with it.
thanks -john
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