summaryrefslogtreecommitdiff
path: root/drivers/hwmon/dell-smm-hwmon.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/hwmon/dell-smm-hwmon.c')
-rw-r--r--drivers/hwmon/dell-smm-hwmon.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
index a34753fc2973..6040a8940674 100644
--- a/drivers/hwmon/dell-smm-hwmon.c
+++ b/drivers/hwmon/dell-smm-hwmon.c
@@ -76,6 +76,9 @@
#define DELL_SMM_NO_TEMP 10
#define DELL_SMM_NO_FANS 4
+/* limit fan multiplier to avoid overflow */
+#define DELL_SMM_MAX_FAN_MULT (INT_MAX / U16_MAX)
+
struct smm_regs {
unsigned int eax;
unsigned int ebx;
@@ -1253,6 +1256,12 @@ static int dell_smm_init_data(struct device *dev, const struct dell_smm_ops *ops
data->ops = ops;
/* All options must not be 0 */
data->i8k_fan_mult = fan_mult ? : I8K_FAN_MULT;
+ if (data->i8k_fan_mult > DELL_SMM_MAX_FAN_MULT) {
+ dev_err(dev,
+ "fan multiplier %u is too large (max %u)\n",
+ data->i8k_fan_mult, DELL_SMM_MAX_FAN_MULT);
+ return -EINVAL;
+ }
data->i8k_fan_max = fan_max ? : I8K_FAN_HIGH;
data->i8k_pwm_mult = DIV_ROUND_UP(255, data->i8k_fan_max);