[PATCH 04/11] usb: xhci-mtk: fix use-after-free of mtk->hcd

[Ikjoon Jang]

On Fri, Jul 30, 2021 at 4:50 PM Chunfeng Yun <chunfeng.yun at mediatek.com> wrote:
>
>  BUG: KASAN: use-after-free in usb_hcd_is_primary_hcd+0x38/0x60
>  Call trace:
>   dump_backtrace+0x0/0x3dc
>   show_stack+0x20/0x2c
>   dump_stack+0x15c/0x1d4
>   print_address_description+0x7c/0x510
>   kasan_report+0x164/0x1ac
>   __asan_report_load8_noabort+0x44/0x50
>   usb_hcd_is_primary_hcd+0x38/0x60
>   xhci_mtk_runtime_suspend+0x68/0x148
>   pm_generic_runtime_suspend+0x90/0xac
>   __rpm_callback+0xb8/0x1f4
>   rpm_callback+0x54/0x1d0
>   rpm_suspend+0x4e0/0xc84
>   __pm_runtime_suspend+0xc4/0x114
>   xhci_mtk_probe+0xa58/0xd00
>
> This may happen when probe fails, needn't suspend it synchronously,
> fix it by using pm_runtime_put_noidle().
>
> Reported-by: Pi Hsun <pihsun at google.com>
> Signed-off-by: Chunfeng Yun <chunfeng.yun at mediatek.com>

Reviewed-and-Tested-by: Ikjoon Jang <ikjn at chromium.org>


> ---
>  drivers/usb/host/xhci-mtk.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c
> index 2548976bcf05..cb27569186a0 100644
> --- a/drivers/usb/host/xhci-mtk.c
> +++ b/drivers/usb/host/xhci-mtk.c
> @@ -569,7 +569,7 @@ static int xhci_mtk_probe(struct platform_device *pdev)
>         xhci_mtk_ldos_disable(mtk);
>
>  disable_pm:
> -       pm_runtime_put_sync_autosuspend(dev);
> +       pm_runtime_put_noidle(dev);
>         pm_runtime_disable(dev);
>         return ret;
>  }
> --
> 2.18.0
>