[PATCH v1 1/1] gpiolib: Fix crash on error in gpiochip_get_ngpios()

[PATCH v1 1/1] gpiolib: Fix crash on error in gpiochip_get_ngpios()

[Andy Shevchenko]

The gpiochip_get_ngpios() uses chip_*() macros to print messages.
However these macros rely on gpiodev to be initialised and set,
which is not the case when called via bgpio_init(). In such a case
the printing messages will crash on NULL pointer dereference.
Replace chip_*() macros by the respective dev_*() ones to avoid
such crash.

Fixes: 55b2395e4e92 ("gpio: mmio: handle "ngpios" properly in bgpio_init()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/gpio/gpiolib.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 98fba0c392ea..d6ebdb2f2e92 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -905,13 +905,13 @@ int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev)
 	}
 
 	if (gc->ngpio == 0) {
-		chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
+		dev_err(dev, "tried to insert a GPIO chip with zero lines\n");
 		return -EINVAL;
 	}
 
 	if (gc->ngpio > FASTPATH_NGPIO)
-		chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
-			gc->ngpio, FASTPATH_NGPIO);
+		dev_warn(dev, "line cnt %u is greater than fast path cnt %u\n",
+			 gc->ngpio, FASTPATH_NGPIO);
 
 	return 0;
 }
-- 
2.45.1.3035.g276e886db78b

Re: [PATCH v1 1/1] gpiolib: Fix crash on error in gpiochip_get_ngpios()

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>


On Thu, 13 Feb 2025 17:56:46 +0200, Andy Shevchenko wrote:
> The gpiochip_get_ngpios() uses chip_*() macros to print messages.
> However these macros rely on gpiodev to be initialised and set,
> which is not the case when called via bgpio_init(). In such a case
> the printing messages will crash on NULL pointer dereference.
> Replace chip_*() macros by the respective dev_*() ones to avoid
> such crash.
> 
> [...]

Eeek! Good catch, queued for fixes.

Bart

[1/1] gpiolib: Fix crash on error in gpiochip_get_ngpios()
      commit: 7b4aebeecbbd5b5fe73e35fad3f62ed21aa7ef44

Best regards,
-- 
Bartosz Golaszewski <bartosz.golaszewski@linaro.org>