On Wed, 1 Sep 2021, Alan Stern wrote:
> From: Michal Kubecek <mkubecek@xxxxxxx>
>
> [patch description by Alan Stern]
>
> Commit 7652dd2c5cb7 ("USB: core: Check buffer length matches wLength
> for control transfers") causes control URB submissions to fail if the
> transfer_buffer_length value disagrees with the setup packet's wLength
> valuel. Unfortunately, it turns out that the usbhid can trigger this
> failure mode when it submits a control request for an input report: It
> pads the transfer buffer size to a multiple of the maxpacket value but
> does not increase wLength correspondingly.
>
> These failures have caused problems for people using an APS UPC, in
> the form of a flood of log messages resembling:
>
> hid-generic 0003:051D:0002.0002: control queue full
>
> This patch fixes the problem by setting the wLength value equal to the
> padded transfer_buffer_length value in hid_submit_ctrl(). As a nice
> bonus, the code which stores the transfer_buffer_length value is now
> shared between the two branches of an "if" statement, so it can be
> de-duplicated.
>
> Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>
> Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> Fixes: 7652dd2c5cb7 ("USB: core: Check buffer length matches wLength for control transfers")
> Tested-by: Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>
> Tested-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
> Acked-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
>
Thanks Alan, applied and I will be sending whole HID tree to Linus soon.
(BTW, something broke your threading, so 2/3 and 3/3 were not threaded
together with 1/3).
--
Jiri Kosina
SUSE Labs
