diff options
| author | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2025-02-10 11:51:57 +0100 |
|---|---|---|
| committer | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2025-02-24 09:58:58 +0100 |
| commit | dcf8f3bffa2de2c7f3b5771b63605194ccd2286f (patch) | |
| tree | 2d42dd0422ef63ee384a6cce78dbb163e3e69ba7 | |
| parent | 69920338f8130da929ade6f93e6fa3e0e68433ee (diff) | |
gpiolib: sanitize the return value of gpio_chip::set_config()
The return value of the set_config() callback may be propagated to
user-space. If a bad driver returns a positive number, it may confuse
user programs. Tighten the API contract and check for positive numbers
returned by GPIO controllers.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-3-12ea88506cb2@linaro.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
| -rw-r--r-- | drivers/gpio/gpiolib.c | 3 | ||||
| -rw-r--r-- | include/linux/gpio/driver.h | 3 |
2 files changed, 5 insertions, 1 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index a98025b0ecf7..67a735d57942 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2593,6 +2593,9 @@ int gpio_do_set_config(struct gpio_desc *desc, unsigned long config) return -ENOTSUPP; ret = guard.gc->set_config(guard.gc, gpio_chip_hwgpio(desc), config); + if (ret > 0) + ret = -EBADE; + #ifdef CONFIG_GPIO_CDEV /* * Special case - if we're setting debounce period, we need to store diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index ce22c072337c..f2145e938b29 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -349,7 +349,8 @@ struct gpio_irq_chip { * @set: assigns output value for signal "offset" * @set_multiple: assigns output values for multiple signals defined by "mask" * @set_config: optional hook for all kinds of settings. Uses the same - * packed config format as generic pinconf. + * packed config format as generic pinconf. Must return 0 on success and + * a negative error number on failure. * @to_irq: optional hook supporting non-static gpiod_to_irq() mappings; * implementation may not sleep * @dbg_show: optional routine to show contents in debugfs; default code |