From: Andrei Lalaev Date: Fri, 15 Apr 2022 07:07:11 +0000 (+0300) Subject: gpiolib: of: fix bounds check for 'gpio-reserved-ranges' X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=e75f88efac05bf4e107e4171d8db6d8c3937252d;p=linux.git gpiolib: of: fix bounds check for 'gpio-reserved-ranges' Gpiolib interprets the elements of "gpio-reserved-ranges" as "start,size" because it clears "size" bits starting from the "start" bit in the according bitmap. So it has to use "greater" instead of "greater or equal" when performs bounds check to make sure that GPIOs are in the available range. Previous implementation skipped ranges that include the last GPIO in the range. I wrote the mail to the maintainers (https://lore.kernel.org/linux-gpio/20220412115554.159435-1-andrei.lalaev@emlid.com/T/#u) of the questioned DTSes (because I couldn't understand how the maintainers interpreted this property), but I haven't received a response. Since the questioned DTSes use "gpio-reserved-ranges = <0 4>" (i.e., the beginning of the range), this patch doesn't affect these DTSes at all. TBH this patch doesn't break any existing DTSes because none of them reserve gpios at the end of range. Fixes: 726cb3ba4969 ("gpiolib: Support 'gpio-reserved-ranges' property") Signed-off-by: Andrei Lalaev Reviewed-by: Andy Shevchenko Reviewed-by: Linus Walleij Cc: stable@vger.kernel.org Signed-off-by: Bartosz Golaszewski --- diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index ae1ce319cd78e..7e5e51d49d09e 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -910,7 +910,7 @@ static void of_gpiochip_init_valid_mask(struct gpio_chip *chip) i, &start); of_property_read_u32_index(np, "gpio-reserved-ranges", i + 1, &count); - if (start >= chip->ngpio || start + count >= chip->ngpio) + if (start >= chip->ngpio || start + count > chip->ngpio) continue; bitmap_clear(chip->valid_mask, start, count);