[PATCH] input/joystick: magellan: Mark __nonstring look-up table

[PATCH] input/joystick: magellan: Mark __nonstring look-up table

[Kees Cook]

GCC 15's new -Wunterminated-string-initialization notices that the
16 character lookup table "nibbles" (which is not used as a C-String)
needs to be marked as "nonstring":

drivers/input/joystick/magellan.c: In function 'magellan_crunch_nibbles':
drivers/input/joystick/magellan.c:51:44: warning: initializer-string for array of 'unsigned char' truncates NUL terminator but destination lacks 'nonstring' attribute (17 chars into 16 available) [-Wunterminated-string-initialization]
   51 |         static unsigned char nibbles[16] = "0AB3D56GH9:K<MN?";
      |                                            ^~~~~~~~~~~~~~~~~~

Add the annotation and While at it, mark the table as const too.

Signed-off-by: Kees Cook <kees@kernel.org>
---
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Erick Archer <erick.archer@outlook.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: linux-input@vger.kernel.org
---
 drivers/input/joystick/magellan.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/input/joystick/magellan.c b/drivers/input/joystick/magellan.c
index 2eaa25c9c68c..7622638e5bb8 100644
--- a/drivers/input/joystick/magellan.c
+++ b/drivers/input/joystick/magellan.c
@@ -48,7 +48,7 @@ struct magellan {
 
 static int magellan_crunch_nibbles(unsigned char *data, int count)
 {
-	static unsigned char nibbles[16] = "0AB3D56GH9:K<MN?";
+	static const unsigned char nibbles[16] __nonstring = "0AB3D56GH9:K<MN?";
 
 	do {
 		if (data[count] == nibbles[data[count] & 0xf])
-- 
2.34.1

Re: [PATCH] input/joystick: magellan: Mark __nonstring look-up table

[Dmitry Torokhov]

On Wed, Apr 16, 2025 at 10:45:17AM -0700, Kees Cook wrote:
> GCC 15's new -Wunterminated-string-initialization notices that the
> 16 character lookup table "nibbles" (which is not used as a C-String)
> needs to be marked as "nonstring":
> 
> drivers/input/joystick/magellan.c: In function 'magellan_crunch_nibbles':
> drivers/input/joystick/magellan.c:51:44: warning: initializer-string for array of 'unsigned char' truncates NUL terminator but destination lacks 'nonstring' attribute (17 chars into 16 available) [-Wunterminated-string-initialization]
>    51 |         static unsigned char nibbles[16] = "0AB3D56GH9:K<MN?";
>       |                                            ^~~~~~~~~~~~~~~~~~
> 
> Add the annotation and While at it, mark the table as const too.
> 
> Signed-off-by: Kees Cook <kees@kernel.org>

Applied, thank you.

-- 
Dmitry