Re: [PATCH] usb: core: handle port status errors in disable_show()
Alan Stern <[email protected]>
| Newsgroups | org.kernel.vger.linux-usb,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
On Sat, Aug 08, 2026 at 03:16:01PM +0200, Karl Mehltretter wrote:
> usb_hub_port_status() leaves its output arguments untouched when the
> status request fails. disable_show() nevertheless uses portstatus, so a
> sysfs read may report the wrong port state instead of an error.
>
> Propagate the status request error.
>
> Fixes: f061f43d7418c ("usb: hub: port: add sysfs entry to switch port power")
> Assisted-by: Claude:claude-fable-5
> Signed-off-by: Karl Mehltretter <[email protected]>
> ---
> drivers/usb/core/port.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
> index b4452b665f591..0022473e526d7 100644
> --- a/drivers/usb/core/port.c
> +++ b/drivers/usb/core/port.c
> @@ -96,7 +96,9 @@ static ssize_t disable_show(struct device *dev,
> goto out_hdev_lock;
> }
>
> - usb_hub_port_status(hub, port1, &portstatus, &unused);
> + rc = usb_hub_port_status(hub, port1, &portstatus, &unused);
> + if (rc < 0)
> + goto out_hdev_lock;
> disabled = !usb_port_is_power_on(hub, portstatus);
>
> out_hdev_lock:
It would be cleaner and simpler to do:
if (rc >= 0)
disabled = !usb_port_is_power_on(hub, portstatus);
Alan Stern