From d6f517e8d866c84bafa60198327e985d55e984de Mon Sep 17 00:00:00 2001 From: Nikita Zhandarovich Date: Wed, 15 Jan 2025 09:12:06 -0800 Subject: [PATCH] mfd: sm501: Switch to BIT() to mitigate integer overflows [ Upstream commit 2d8cb9ffe18c2f1e5bd07a19cbce85b26c1d0cf0 ] If offset end up being high enough, right hand expression in functions like sm501_gpio_set() shifted left for that number of bits, may not fit in int type. Just in case, fix that by using BIT() both as an option safe from overflow issues and to make this step look similar to other gpio drivers. Found by Linux Verification Center (linuxtesting.org) with static analysis tool SVACE. Fixes: f61be273d369 ("sm501: add gpiolib support") Signed-off-by: Nikita Zhandarovich Link: https://lore.kernel.org/r/20250115171206.20308-1-n.zhandarovich@fintech.ru Signed-off-by: Lee Jones Signed-off-by: Sasha Levin --- drivers/mfd/sm501.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/mfd/sm501.c b/drivers/mfd/sm501.c index 28027982cf693..509dcb226cbfb 100644 --- a/drivers/mfd/sm501.c +++ b/drivers/mfd/sm501.c @@ -920,7 +920,7 @@ static void sm501_gpio_set(struct gpio_chip *chip, unsigned offset, int value) { struct sm501_gpio_chip *smchip = gpiochip_get_data(chip); struct sm501_gpio *smgpio = smchip->ourgpio; - unsigned long bit = 1 << offset; + unsigned long bit = BIT(offset); void __iomem *regs = smchip->regbase; unsigned long save; unsigned long val; @@ -946,7 +946,7 @@ static int sm501_gpio_input(struct gpio_chip *chip, unsigned offset) struct sm501_gpio_chip *smchip = gpiochip_get_data(chip); struct sm501_gpio *smgpio = smchip->ourgpio; void __iomem *regs = smchip->regbase; - unsigned long bit = 1 << offset; + unsigned long bit = BIT(offset); unsigned long save; unsigned long ddr; @@ -971,7 +971,7 @@ static int sm501_gpio_output(struct gpio_chip *chip, { struct sm501_gpio_chip *smchip = gpiochip_get_data(chip); struct sm501_gpio *smgpio = smchip->ourgpio; - unsigned long bit = 1 << offset; + unsigned long bit = BIT(offset); void __iomem *regs = smchip->regbase; unsigned long save; unsigned long val; -- 2.47.3