[PATCH] drivers: hid: Remove dead storage

[PATCH] drivers: hid: Remove dead storage

[Tapasweni Pathak]

Remove storing of return value of ntrig_version_string function
to ret as it is a dead storage and not used afterwards.

Found using Facebook's Infer. Build tested it.

Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
---
There is another option to instead check for non zero return
value for ntrig_version_string() as a successful completion
of the function. ntrig_version_string() returns the length
of output printed by sprintf() after converting the raw firmware
code into a 5 comma separated numbers.

 drivers/hid/hid-ntrig.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
index 43b1c72..22aebf4 100644
--- a/drivers/hid/hid-ntrig.c
+++ b/drivers/hid/hid-ntrig.c
@@ -159,7 +159,7 @@ static void ntrig_report_version(struct hid_device *hdev)
 			      USB_CTRL_SET_TIMEOUT);

 	if (ret == 8) {
-		ret = ntrig_version_string(&data[2], buf);
+		ntrig_version_string(&data[2], buf);

 		hid_info(hdev, "Firmware version: %s (%02x%02x %02x%02x)\n",
 			 buf, data[2], data[3], data[4], data[5]);
--
2.7.4

Re: [PATCH] drivers: hid: Remove dead storage

[Benjamin Tissoires]

On Sat, Sep 29, 2018 at 6:06 PM Tapasweni Pathak
<tapaswenipathak@gmail.com> wrote:
>
> Remove storing of return value of ntrig_version_string function
> to ret as it is a dead storage and not used afterwards.
>
> Found using Facebook's Infer. Build tested it.
>
> Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
> ---
> There is another option to instead check for non zero return
> value for ntrig_version_string() as a successful completion
> of the function. ntrig_version_string() returns the length
> of output printed by sprintf() after converting the raw firmware
> code into a 5 comma separated numbers.

If you really want to fix this, I would prefer the alternative above.

Just one nitpick: please make sure ntrig_version_string() returns
either 0 (success) or a negative error.
Then in ntrig_report_version(), if the returned value is non null,
output a hid_warn() instead of leaking a non allocated buffer.

Cheers,
Benjamin

>
>  drivers/hid/hid-ntrig.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
> index 43b1c72..22aebf4 100644
> --- a/drivers/hid/hid-ntrig.c
> +++ b/drivers/hid/hid-ntrig.c
> @@ -159,7 +159,7 @@ static void ntrig_report_version(struct hid_device *hdev)
>                               USB_CTRL_SET_TIMEOUT);
>
>         if (ret == 8) {
> -               ret = ntrig_version_string(&data[2], buf);
> +               ntrig_version_string(&data[2], buf);
>
>                 hid_info(hdev, "Firmware version: %s (%02x%02x %02x%02x)\n",
>                          buf, data[2], data[3], data[4], data[5]);
> --
> 2.7.4