[PATCH] HID: uclogic: Fix frame templates for big endian architectures

[PATCH] HID: uclogic: Fix frame templates for big endian architectures

[José Expósito]

When parsing a frame template with a placeholder indicating the number
of buttons present on the frame its value was incorrectly set on big
endian architectures due to double little endian conversion.

In order to reproduce the issue and verify the fix, run the HID KUnit
tests on the PowerPC architecture:

  $ ./tools/testing/kunit/kunit.py run --kunitconfig=drivers/hid \
    --arch=powerpc --cross_compile=powerpc64-linux-gnu-

Fixes: 867c89254425 ("HID: uclogic: Allow to generate frame templates")
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
---
 drivers/hid/hid-uclogic-rdesc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/hid-uclogic-rdesc.c b/drivers/hid/hid-uclogic-rdesc.c
index 4bd54c4fb5b0..6b73eb0df6bd 100644
--- a/drivers/hid/hid-uclogic-rdesc.c
+++ b/drivers/hid/hid-uclogic-rdesc.c
@@ -1193,7 +1193,7 @@ __u8 *uclogic_rdesc_template_apply(const __u8 *template_ptr,
 			   p[sizeof(btn_head)] < param_num) {
 			v = param_list[p[sizeof(btn_head)]];
 			put_unaligned((__u8)0x2A, p); /* Usage Maximum */
-			put_unaligned_le16((__force u16)cpu_to_le16(v), p + 1);
+			put_unaligned((__force u16)cpu_to_le16(v), (s16 *)(p + 1));
 			p += sizeof(btn_head) + 1;
 		} else {
 			p++;
-- 
2.25.1

Re: [PATCH] HID: uclogic: Fix frame templates for big endian architectures

[Jiri Kosina]

On Thu, 10 Nov 2022, José Expósito wrote:

> When parsing a frame template with a placeholder indicating the number
> of buttons present on the frame its value was incorrectly set on big
> endian architectures due to double little endian conversion.
> 
> In order to reproduce the issue and verify the fix, run the HID KUnit
> tests on the PowerPC architecture:
> 
>   $ ./tools/testing/kunit/kunit.py run --kunitconfig=drivers/hid \
>     --arch=powerpc --cross_compile=powerpc64-linux-gnu-
> 
> Fixes: 867c89254425 ("HID: uclogic: Allow to generate frame templates")
> Signed-off-by: José Expósito <jose.exposito89@gmail.com>
> ---
>  drivers/hid/hid-uclogic-rdesc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/hid/hid-uclogic-rdesc.c b/drivers/hid/hid-uclogic-rdesc.c
> index 4bd54c4fb5b0..6b73eb0df6bd 100644
> --- a/drivers/hid/hid-uclogic-rdesc.c
> +++ b/drivers/hid/hid-uclogic-rdesc.c
> @@ -1193,7 +1193,7 @@ __u8 *uclogic_rdesc_template_apply(const __u8 *template_ptr,
>  			   p[sizeof(btn_head)] < param_num) {
>  			v = param_list[p[sizeof(btn_head)]];
>  			put_unaligned((__u8)0x2A, p); /* Usage Maximum */
> -			put_unaligned_le16((__force u16)cpu_to_le16(v), p + 1);
> +			put_unaligned((__force u16)cpu_to_le16(v), (s16 *)(p + 1));
>  			p += sizeof(btn_head) + 1;
>  		} else {

Applied to hid.git#for-6.1/upstream-fixes, thanks José.

-- 
Jiri Kosina
SUSE Labs