| Message ID | 20170906154756.2133726-1-arnd@arndb.de |
|---|---|
| State | New |
| Headers | show |
| Series | gpio: acpi: work around false-positive -Wstring-overflow warning | expand |
On Wed, 2017-09-06 at 17:47 +0200, Arnd Bergmann wrote: > gcc-7 notices that the pin_table is an array of 16-bit numbers, > but fails to take the following range check into account: > > drivers/gpio/gpiolib-acpi.c: In function 'acpi_gpiochip_request_interrupt': > drivers/gpio/gpiolib-acpi.c:206:24: warning: '%02X' directive writing between 2 and 4 bytes into a region of size 3 [-Wformat-overflow=] > sprintf(ev_name, "_%c%02X", > ^~~~ > drivers/gpio/gpiolib-acpi.c:206:20: note: directive argument in the range [0, 65535] > sprintf(ev_name, "_%c%02X", > ^~~~~~~~~ > drivers/gpio/gpiolib-acpi.c:206:3: note: 'sprintf' output between 5 and 7 bytes into a destination of size 5 > sprintf(ev_name, "_%c%02X", > ^~~~~~~~~~~~~~~~~~~~~~~~~~~ > agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L', > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > pin); > ~~~~ > > As suggested by Andy, this changes the format string to have a fixed length. > Since modifying the range check did not help, I also opened a bug against > gcc, see link below. The code has int pin does changing pin to unsigned int matter? > diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c [] > @@ -203,7 +203,7 @@ static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares, > > if (pin <= 255) { > char ev_name[5]; > - sprintf(ev_name, "_%c%02X", > + sprintf(ev_name, "_%c%02hhX", > agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L', > pin); > if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle))) -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Sep 6, 2017 at 5:52 PM, Joe Perches <joe@perches.com> wrote: > On Wed, 2017-09-06 at 17:47 +0200, Arnd Bergmann wrote: >> As suggested by Andy, this changes the format string to have a fixed length. >> Since modifying the range check did not help, I also opened a bug against >> gcc, see link below. > > The code has > > int pin > > does changing pin to unsigned int matter? No difference, see also the gcc bugzilla report. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, 2017-09-06 at 21:53 +0200, Arnd Bergmann wrote: > On Wed, Sep 6, 2017 at 5:52 PM, Joe Perches <joe@perches.com> wrote: > > On Wed, 2017-09-06 at 17:47 +0200, Arnd Bergmann wrote: > > > As suggested by Andy, this changes the format string to have a fixed length. > > > Since modifying the range check did not help, I also opened a bug against > > > gcc, see link below. > > > > The code has > > > > int pin > > > > does changing pin to unsigned int matter? > > No difference, see also the gcc bugzilla report. Perhaps the bug report does not apply here as the function is casting a unsigned int to an int through a pointer when the int could now be negative, the int is tested for < 256 and is then printed. -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Sep 06, 2017 at 05:47:45PM +0200, Arnd Bergmann wrote: > gcc-7 notices that the pin_table is an array of 16-bit numbers, > but fails to take the following range check into account: > > drivers/gpio/gpiolib-acpi.c: In function 'acpi_gpiochip_request_interrupt': > drivers/gpio/gpiolib-acpi.c:206:24: warning: '%02X' directive writing between 2 and 4 bytes into a region of size 3 [-Wformat-overflow=] > sprintf(ev_name, "_%c%02X", > ^~~~ > drivers/gpio/gpiolib-acpi.c:206:20: note: directive argument in the range [0, 65535] > sprintf(ev_name, "_%c%02X", > ^~~~~~~~~ > drivers/gpio/gpiolib-acpi.c:206:3: note: 'sprintf' output between 5 and 7 bytes into a destination of size 5 > sprintf(ev_name, "_%c%02X", > ^~~~~~~~~~~~~~~~~~~~~~~~~~~ > agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L', > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > pin); > ~~~~ > > As suggested by Andy, this changes the format string to have a fixed length. > Since modifying the range check did not help, I also opened a bug against > gcc, see link below. > > Fixes: 0d1c28a449c6 ("gpiolib-acpi: Add ACPI5 event model support to gpio.") > Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Link: https://patchwork.kernel.org/patch/9840801/ > Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82123 > Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Sep 6, 2017 at 5:47 PM, Arnd Bergmann <arnd@arndb.de> wrote: > gcc-7 notices that the pin_table is an array of 16-bit numbers, > but fails to take the following range check into account: > > drivers/gpio/gpiolib-acpi.c: In function 'acpi_gpiochip_request_interrupt': > drivers/gpio/gpiolib-acpi.c:206:24: warning: '%02X' directive writing between 2 and 4 bytes into a region of size 3 [-Wformat-overflow=] > sprintf(ev_name, "_%c%02X", > ^~~~ > drivers/gpio/gpiolib-acpi.c:206:20: note: directive argument in the range [0, 65535] > sprintf(ev_name, "_%c%02X", > ^~~~~~~~~ > drivers/gpio/gpiolib-acpi.c:206:3: note: 'sprintf' output between 5 and 7 bytes into a destination of size 5 > sprintf(ev_name, "_%c%02X", > ^~~~~~~~~~~~~~~~~~~~~~~~~~~ > agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L', > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > pin); > ~~~~ > > As suggested by Andy, this changes the format string to have a fixed length. > Since modifying the range check did not help, I also opened a bug against > gcc, see link below. > > Fixes: 0d1c28a449c6 ("gpiolib-acpi: Add ACPI5 event model support to gpio.") > Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Link: https://patchwork.kernel.org/patch/9840801/ > Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82123 > Signed-off-by: Arnd Bergmann <arnd@arndb.de> Patch applied with Mika's ACK. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index 4d2113530735..eb4528c87c0b 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -203,7 +203,7 @@ static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares, if (pin <= 255) { char ev_name[5]; - sprintf(ev_name, "_%c%02X", + sprintf(ev_name, "_%c%02hhX", agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L', pin); if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
gcc-7 notices that the pin_table is an array of 16-bit numbers, but fails to take the following range check into account: drivers/gpio/gpiolib-acpi.c: In function 'acpi_gpiochip_request_interrupt': drivers/gpio/gpiolib-acpi.c:206:24: warning: '%02X' directive writing between 2 and 4 bytes into a region of size 3 [-Wformat-overflow=] sprintf(ev_name, "_%c%02X", ^~~~ drivers/gpio/gpiolib-acpi.c:206:20: note: directive argument in the range [0, 65535] sprintf(ev_name, "_%c%02X", ^~~~~~~~~ drivers/gpio/gpiolib-acpi.c:206:3: note: 'sprintf' output between 5 and 7 bytes into a destination of size 5 sprintf(ev_name, "_%c%02X", ^~~~~~~~~~~~~~~~~~~~~~~~~~~ agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L', ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ pin); ~~~~ As suggested by Andy, this changes the format string to have a fixed length. Since modifying the range check did not help, I also opened a bug against gcc, see link below. Fixes: 0d1c28a449c6 ("gpiolib-acpi: Add ACPI5 event model support to gpio.") Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://patchwork.kernel.org/patch/9840801/ Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82123 Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/gpio/gpiolib-acpi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)