* [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning
@ 2017-09-06 15:47 Arnd Bergmann
2017-09-06 15:52 ` Joe Perches
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Arnd Bergmann @ 2017-09-06 15:47 UTC (permalink / raw)
To: Mika Westerberg, Andy Shevchenko, Linus Walleij
Cc: Arnd Bergmann, Dmitry Torokhov, Hans de Goede, Wei Yongjun,
linux-gpio, linux-acpi, linux-kernel
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(-)
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)))
--
2.9.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning
2017-09-06 15:47 [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning Arnd Bergmann
@ 2017-09-06 15:52 ` Joe Perches
2017-09-06 19:53 ` Arnd Bergmann
2017-09-07 6:50 ` Mika Westerberg
2017-09-12 9:26 ` Linus Walleij
2 siblings, 1 reply; 6+ messages in thread
From: Joe Perches @ 2017-09-06 15:52 UTC (permalink / raw)
To: Arnd Bergmann, Mika Westerberg, Andy Shevchenko, Linus Walleij
Cc: Dmitry Torokhov, Hans de Goede, Wei Yongjun, linux-gpio,
linux-acpi, linux-kernel
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)))
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning
2017-09-06 15:52 ` Joe Perches
@ 2017-09-06 19:53 ` Arnd Bergmann
2017-09-06 23:42 ` Joe Perches
0 siblings, 1 reply; 6+ messages in thread
From: Arnd Bergmann @ 2017-09-06 19:53 UTC (permalink / raw)
To: Joe Perches
Cc: Mika Westerberg, Andy Shevchenko, Linus Walleij, Dmitry Torokhov,
Hans de Goede, Wei Yongjun, linux-gpio, ACPI Devel Maling List,
Linux Kernel Mailing List
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
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning
2017-09-06 19:53 ` Arnd Bergmann
@ 2017-09-06 23:42 ` Joe Perches
0 siblings, 0 replies; 6+ messages in thread
From: Joe Perches @ 2017-09-06 23:42 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Mika Westerberg, Andy Shevchenko, Linus Walleij, Dmitry Torokhov,
Hans de Goede, Wei Yongjun, linux-gpio, ACPI Devel Maling List,
Linux Kernel Mailing List
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.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning
2017-09-06 15:47 [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning Arnd Bergmann
2017-09-06 15:52 ` Joe Perches
@ 2017-09-07 6:50 ` Mika Westerberg
2017-09-12 9:26 ` Linus Walleij
2 siblings, 0 replies; 6+ messages in thread
From: Mika Westerberg @ 2017-09-07 6:50 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Andy Shevchenko, Linus Walleij, Dmitry Torokhov, Hans de Goede,
Wei Yongjun, linux-gpio, linux-acpi, linux-kernel
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>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning
2017-09-06 15:47 [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning Arnd Bergmann
2017-09-06 15:52 ` Joe Perches
2017-09-07 6:50 ` Mika Westerberg
@ 2017-09-12 9:26 ` Linus Walleij
2 siblings, 0 replies; 6+ messages in thread
From: Linus Walleij @ 2017-09-12 9:26 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Mika Westerberg, Andy Shevchenko, Dmitry Torokhov, Hans de Goede,
Wei Yongjun, linux-gpio@vger.kernel.org, ACPI Devel Maling List,
linux-kernel@vger.kernel.org
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
^ permalink raw reply [flat|nested] 6+ messages in thread
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2017-09-06 15:47 [PATCH] gpio: acpi: work around false-positive -Wstring-overflow warning Arnd Bergmann
2017-09-06 15:52 ` Joe Perches
2017-09-06 19:53 ` Arnd Bergmann
2017-09-06 23:42 ` Joe Perches
2017-09-07 6:50 ` Mika Westerberg
2017-09-12 9:26 ` Linus Walleij
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