diff options
| author |   Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2025-02-10 11:51:55 +0100 |
|---|---|---|
| committer | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2025-02-17 11:50:50 +0100 |
| commit | 9d846b1aebbe488f245f1aa463802ff9c34cc078 (patch) | |
| tree | 6918ab75b1d9b32c849dfb0154b376de1cfd064c | |
| parent | Linux 6.14-rc3 (diff) | |
| download | wireguard-linux-9d846b1aebbe488f245f1aa463802ff9c34cc078.tar.xz wireguard-linux-9d846b1aebbe488f245f1aa463802ff9c34cc078.zip | |
gpiolib: check the return value of gpio_chip::get_direction()
As per the API contract - gpio_chip::get_direction() may fail and return
a negative error number. However, we treat it as if it always returned 0
or 1. Check the return value of the callback and propagate the error
number up the stack.
Cc: stable@vger.kernel.org
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-1-12ea88506cb2@linaro.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Diffstat (limited to '')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 44 |
1 files changed, 29 insertions, 15 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index ca2f58a2cd45..29110dc436f1 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1057,8 +1057,11 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, desc->gdev = gdev; if (gc->get_direction && gpiochip_line_is_valid(gc, desc_index)) { - assign_bit(FLAG_IS_OUT, - &desc->flags, !gc->get_direction(gc, desc_index)); + ret = gc->get_direction(gc, desc_index); + if (ret < 0) + goto err_cleanup_desc_srcu; + + assign_bit(FLAG_IS_OUT, &desc->flags, !ret); } else { assign_bit(FLAG_IS_OUT, &desc->flags, !gc->direction_input); @@ -2728,13 +2731,18 @@ int gpiod_direction_input_nonotify(struct gpio_desc *desc) if (guard.gc->direction_input) { ret = guard.gc->direction_input(guard.gc, gpio_chip_hwgpio(desc)); - } else if (guard.gc->get_direction && - (guard.gc->get_direction(guard.gc, - gpio_chip_hwgpio(desc)) != 1)) { - gpiod_warn(desc, - "%s: missing direction_input() operation and line is output\n", - __func__); - return -EIO; + } else if (guard.gc->get_direction) { + ret = guard.gc->get_direction(guard.gc, + gpio_chip_hwgpio(desc)); + if (ret < 0) + return ret; + + if (ret != GPIO_LINE_DIRECTION_IN) { + gpiod_warn(desc, + "%s: missing direction_input() operation and line is output\n", + __func__); + return -EIO; + } } if (ret == 0) { clear_bit(FLAG_IS_OUT, &desc->flags); @@ -2771,12 +2779,18 @@ static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) gpio_chip_hwgpio(desc), val); } else { /* Check that we are in output mode if we can */ - if (guard.gc->get_direction && - guard.gc->get_direction(guard.gc, gpio_chip_hwgpio(desc))) { - gpiod_warn(desc, - "%s: missing direction_output() operation\n", - __func__); - return -EIO; + if (guard.gc->get_direction) { + ret = guard.gc->get_direction(guard.gc, + gpio_chip_hwgpio(desc)); + if (ret < 0) + return ret; + + if (ret != GPIO_LINE_DIRECTION_OUT) { + gpiod_warn(desc, + "%s: missing direction_output() operation\n", + __func__); + return -EIO; + } } /* * If we can't actively set the direction, we are some |