| Message ID | 20210927101416.1569609-1-arnd@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | [RESEND,v2] Input: analog - fix invalid snprintf() call | expand |
On Mon, Sep 27, 2021 at 12:14:06PM +0200, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@arndb.de> > > Overlapping input and output arguments to snprintf() are > undefined behavior in C99: > > drivers/input/joystick/analog.c: In function 'analog_name': > drivers/input/joystick/analog.c:428:3: error: 'snprintf' argument 4 overlaps destination object 'analog' [-Werror=restrict] > 428 | snprintf(analog->name, sizeof(analog->name), "%s %d-hat", > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > 429 | analog->name, hweight16(analog->mask & ANALOG_HATS_ALL)); > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > drivers/input/joystick/analog.c:420:40: note: destination object referenced by 'restrict'-qualified argument 1 was declared here > 420 | static void analog_name(struct analog *analog) > | ~~~~~~~~~~~~~~~^~~~~~ > > Change this function to use the simpler seq_buf interface instead. > > Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk> > Link: https://lore.kernel.org/all/20210323131456.2600132-1-arnd@kernel.org/ > Link: https://lore.kernel.org/all/20210324131959.2089129-1-arnd@kernel.org/ > Signed-off-by: Arnd Bergmann <arnd@arndb.de> Applied, thank you. -- Dmitry
diff --git a/drivers/input/joystick/analog.c b/drivers/input/joystick/analog.c index 882c3c8ba399..3c17bf202af5 100644 --- a/drivers/input/joystick/analog.c +++ b/drivers/input/joystick/analog.c @@ -19,6 +19,7 @@ #include <linux/input.h> #include <linux/gameport.h> #include <linux/jiffies.h> +#include <linux/seq_buf.h> #include <linux/timex.h> #include <linux/timekeeping.h> @@ -338,23 +339,24 @@ static void analog_calibrate_timer(struct analog_port *port) static void analog_name(struct analog *analog) { - snprintf(analog->name, sizeof(analog->name), "Analog %d-axis %d-button", + struct seq_buf s; + + seq_buf_init(&s, analog->name, sizeof(analog->name)); + seq_buf_printf(&s, "Analog %d-axis %d-button", hweight8(analog->mask & ANALOG_AXES_STD), hweight8(analog->mask & ANALOG_BTNS_STD) + !!(analog->mask & ANALOG_BTNS_CHF) * 2 + hweight16(analog->mask & ANALOG_BTNS_GAMEPAD) + !!(analog->mask & ANALOG_HBTN_CHF) * 4); if (analog->mask & ANALOG_HATS_ALL) - snprintf(analog->name, sizeof(analog->name), "%s %d-hat", - analog->name, hweight16(analog->mask & ANALOG_HATS_ALL)); + seq_buf_printf(&s, " %d-hat", + hweight16(analog->mask & ANALOG_HATS_ALL)); if (analog->mask & ANALOG_HAT_FCS) - strlcat(analog->name, " FCS", sizeof(analog->name)); + seq_buf_printf(&s, " FCS"); if (analog->mask & ANALOG_ANY_CHF) - strlcat(analog->name, (analog->mask & ANALOG_SAITEK) ? " Saitek" : " CHF", - sizeof(analog->name)); + seq_buf_printf(&s, (analog->mask & ANALOG_SAITEK) ? " Saitek" : " CHF"); - strlcat(analog->name, (analog->mask & ANALOG_GAMEPAD) ? " gamepad": " joystick", - sizeof(analog->name)); + seq_buf_printf(&s, (analog->mask & ANALOG_GAMEPAD) ? " gamepad": " joystick"); } /*