2023-06-13 10:28:42

by Nikita Zhandarovich

[permalink] [raw]
Subject: [PATCH] HID: logitech-dj: Fix error handling in logi_dj_recv_switch_to_dj_mode()

Presently, if a call to logi_dj_recv_send_report() fails, we do
not learn about the error until after sending short
HID_OUTPUT_REPORT with hid_hw_raw_request().
To handle this somewhat unlikely issue, return on error in
logi_dj_recv_send_report() (minding ugly sleep workaround) and
take into account the result of hid_hw_raw_request().

Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.

Fixes: 6a9ddc897883 ("HID: logitech-dj: enable notifications on connect/disconnect")
Signed-off-by: Nikita Zhandarovich <[email protected]>
---
drivers/hid/hid-logitech-dj.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-logitech-dj.c b/drivers/hid/hid-logitech-dj.c
index 62180414efcc..e6a8b6d8eab7 100644
--- a/drivers/hid/hid-logitech-dj.c
+++ b/drivers/hid/hid-logitech-dj.c
@@ -1285,6 +1285,9 @@ static int logi_dj_recv_switch_to_dj_mode(struct dj_receiver_dev *djrcv_dev,
* 50 msec should gives enough time to the receiver to be ready.
*/
msleep(50);
+
+ if (retval)
+ return retval;
}

/*
@@ -1306,7 +1309,7 @@ static int logi_dj_recv_switch_to_dj_mode(struct dj_receiver_dev *djrcv_dev,
buf[5] = 0x09;
buf[6] = 0x00;

- hid_hw_raw_request(hdev, REPORT_ID_HIDPP_SHORT, buf,
+ retval = hid_hw_raw_request(hdev, REPORT_ID_HIDPP_SHORT, buf,
HIDPP_REPORT_SHORT_LENGTH, HID_OUTPUT_REPORT,
HID_REQ_SET_REPORT);

--
2.25.1



2023-08-14 09:36:58

by Jiri Kosina

[permalink] [raw]
Subject: Re: [PATCH] HID: logitech-dj: Fix error handling in logi_dj_recv_switch_to_dj_mode()

On Tue, 13 Jun 2023, Nikita Zhandarovich wrote:

> Presently, if a call to logi_dj_recv_send_report() fails, we do
> not learn about the error until after sending short
> HID_OUTPUT_REPORT with hid_hw_raw_request().
> To handle this somewhat unlikely issue, return on error in
> logi_dj_recv_send_report() (minding ugly sleep workaround) and
> take into account the result of hid_hw_raw_request().
>
> Found by Linux Verification Center (linuxtesting.org) with static
> analysis tool SVACE.
>
> Fixes: 6a9ddc897883 ("HID: logitech-dj: enable notifications on connect/disconnect")
> Signed-off-by: Nikita Zhandarovich <[email protected]>
> ---
> drivers/hid/hid-logitech-dj.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hid/hid-logitech-dj.c b/drivers/hid/hid-logitech-dj.c
> index 62180414efcc..e6a8b6d8eab7 100644
> --- a/drivers/hid/hid-logitech-dj.c
> +++ b/drivers/hid/hid-logitech-dj.c
> @@ -1285,6 +1285,9 @@ static int logi_dj_recv_switch_to_dj_mode(struct dj_receiver_dev *djrcv_dev,
> * 50 msec should gives enough time to the receiver to be ready.
> */
> msleep(50);
> +
> + if (retval)
> + return retval;
> }
>
> /*
> @@ -1306,7 +1309,7 @@ static int logi_dj_recv_switch_to_dj_mode(struct dj_receiver_dev *djrcv_dev,
> buf[5] = 0x09;
> buf[6] = 0x00;
>
> - hid_hw_raw_request(hdev, REPORT_ID_HIDPP_SHORT, buf,
> + retval = hid_hw_raw_request(hdev, REPORT_ID_HIDPP_SHORT, buf,
> HIDPP_REPORT_SHORT_LENGTH, HID_OUTPUT_REPORT,
> HID_REQ_SET_REPORT);

Looks good to me. Benjamin, could you please Ack/apply it?

Thanks,

--
Jiri Kosina
SUSE Labs


2023-08-22 18:56:48

by Benjamin Tissoires

[permalink] [raw]
Subject: Re: [PATCH] HID: logitech-dj: Fix error handling in logi_dj_recv_switch_to_dj_mode()

On Tue, 13 Jun 2023 03:16:35 -0700, Nikita Zhandarovich wrote:
> Presently, if a call to logi_dj_recv_send_report() fails, we do
> not learn about the error until after sending short
> HID_OUTPUT_REPORT with hid_hw_raw_request().
> To handle this somewhat unlikely issue, return on error in
> logi_dj_recv_send_report() (minding ugly sleep workaround) and
> take into account the result of hid_hw_raw_request().
>
> [...]

Applied to hid/hid.git (for-6.6/logitech), thanks!

[1/1] HID: logitech-dj: Fix error handling in logi_dj_recv_switch_to_dj_mode()
https://git.kernel.org/hid/hid/c/6f20d3261265

Cheers,
--
Benjamin Tissoires <[email protected]>