From d105f30bea9104c590a9e5b495cb8a49bdfe405f Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Wed, 17 Nov 2021 09:51:47 -0800 Subject: [PATCH] hwmon: (lm90) Prevent integer overflow/underflow in hysteresis calculations [ Upstream commit 55840b9eae5367b5d5b29619dc2fb7e4596dba46 ] Commit b50aa49638c7 ("hwmon: (lm90) Prevent integer underflows of temperature calculations") addressed a number of underflow situations when writing temperature limits. However, it missed one situation, seen when an attempt is made to set the hysteresis value to MAX_LONG and the critical temperature limit is negative. Use clamp_val() when setting the hysteresis temperature to ensure that the provided value can never overflow or underflow. Fixes: b50aa49638c7 ("hwmon: (lm90) Prevent integer underflows of temperature calculations") Cc: Dmitry Osipenko Reviewed-by: Dmitry Osipenko Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/lm90.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c index d40e3bb..f6e6c7c 100644 --- a/drivers/hwmon/lm90.c +++ b/drivers/hwmon/lm90.c @@ -1143,8 +1143,8 @@ static int lm90_set_temphyst(struct lm90_data *data, long val) else temp = temp_from_s8(data->temp8[LOCAL_CRIT]); - /* prevent integer underflow */ - val = max(val, -128000l); + /* prevent integer overflow/underflow */ + val = clamp_val(val, -128000l, 255000l); data->temp_hyst = hyst_to_reg(temp - val); err = i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST, -- 2.7.4