On Mon, 2021-08-09 at 15:32 +0800, Ikjoon Jang wrote:
> Hi Chunfeng,
>
> On Fri, Jul 30, 2021 at 4:50 PM Chunfeng Yun <
> chunfeng.yun@xxxxxxxxxxxx> wrote:
> >
> > check_sch_tt() will access fs_bus_bw[] array, check boundary
> > firstly to avoid out-of-bounds issue.
> >
> > Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
> > ---
> > drivers/usb/host/xhci-mtk-sch.c | 7 ++++---
> > 1 file changed, 4 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/usb/host/xhci-mtk-sch.c
> > b/drivers/usb/host/xhci-mtk-sch.c
> > index 10c0f0f6461f..c2f13d69c607 100644
> > --- a/drivers/usb/host/xhci-mtk-sch.c
> > +++ b/drivers/usb/host/xhci-mtk-sch.c
> > @@ -600,13 +600,14 @@ static int check_sch_bw(struct
> > mu3h_sch_bw_info *sch_bw,
> > * and find a microframe where its worst bandwidth is
> > minimum.
> > */
> > for (offset = 0; offset < sch_ep->esit; offset++) {
> > - ret = check_sch_tt(sch_ep, offset);
> > - if (ret)
> > - continue;
> >
> > if ((offset + sch_ep->num_budget_microframes) >
> > esit_boundary)
> > break;
>
> Instead of dropping it,
> I'm wondering if it should be checked against (offset & 63) == 0 when
> it's 64?
No, sch_ep->esit already ensure it, it's <= 64, see get_esit()
>
> >
> > + ret = check_sch_tt(sch_ep, offset);
> > + if (ret)
> > + continue;
> > +
> > worst_bw = get_max_bw(sch_bw, sch_ep, offset);
> > if (worst_bw > bw_boundary)
> > continue;
> > --
> > 2.18.0
> >
