hwmon: (mlxreg-fan) Fix out of bounds read on array fan->pwm

Array fan->pwm[] is MLXREG_FAN_MAX_PWM elements in size, however the
for-loop has a off-by-one error causing index i to be out of range
causing an out of bounds read on the array. Fix this by replacing
the <= operator with < in the for-loop.

Addresses-Coverity: ("Out-of-bounds read")
Reported-by: Vadim Pasternak <vadimp@nvidia.com>
Fixes: 35edbaab3bbf ("hwmon: (mlxreg-fan) Extend driver to support multiply cooling devices")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210920180921.16246-1-colin.king@canonical.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/mlxreg-fan.c b/drivers/hwmon/mlxreg-fan.c
index 35228ed..feab9ec 100644 (file)
--- a/drivers/hwmon/mlxreg-fan.c
+++ b/drivers/hwmon/mlxreg-fan.c
@@ -554,7 +554,7 @@ static int mlxreg_fan_cooling_config(struct device *dev, struct mlxreg_fan *fan)
 {
        int i, j;
 
-       for (i = 0; i <= MLXREG_FAN_MAX_PWM; i++) {
+       for (i = 0; i < MLXREG_FAN_MAX_PWM; i++) {
                struct mlxreg_fan_pwm *pwm = &fan->pwm[i];
 
                if (!pwm->connected)