Re: [PATCH 09/11] usb: xhci-mtk: check boundary before check tt
From: Ikjoon Jang <hidden>
Date: 2021-08-09 07:32:48
Also in:
linux-arm-kernel, linux-mediatek, linux-usb, lkml
Hi Chunfeng, On Fri, Jul 30, 2021 at 4:50 PM Chunfeng Yun [off-list ref] wrote:
quoted hunk ↗ jump to hunk
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@mediatek.com> --- 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?
+ 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