hwmon: (adt7475) Potential error pointer dereferences (9d19371d) · Commits · 戴 / test

The adt7475_update_device() function returns error pointers. The problem is that in show_pwmfreq() we dereference it before the check. And then in pwm_use_point2_pwm_at_crit_show() there isn't a check at all. I don't know if it's required, but it silences a static checker warning and it's doesn't hurt anything to check. Signed-off-by:

Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by:

Tokunori Ikegami <ikegami@allied-telesis.co.jp> Signed-off-by:

Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/adt7475.c

+8 −3

Original line number	Diff line number	Diff line
		@@ -962,13 +962,14 @@ static ssize_t show_pwmfreq(struct device dev, struct device_attribute attr,
		{
		struct adt7475_data *data = adt7475_update_device(dev);
		struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
		int i = clamp_val(data->range[sattr->index] & 0xf, 0,
		ARRAY_SIZE(pwmfreq_table) - 1);
		int idx;

		if (IS_ERR(data))
		return PTR_ERR(data);
		idx = clamp_val(data->range[sattr->index] & 0xf, 0,
		ARRAY_SIZE(pwmfreq_table) - 1);

		return sprintf(buf, "%d\n", pwmfreq_table[i]);
		return sprintf(buf, "%d\n", pwmfreq_table[idx]);
		}

		static ssize_t set_pwmfreq(struct device dev, struct device_attribute attr,
		@@ -1004,6 +1005,10 @@ static ssize_t pwm_use_point2_pwm_at_crit_show(struct device *dev,
		char *buf)
		{
		struct adt7475_data *data = adt7475_update_device(dev);

		if (IS_ERR(data))
		return PTR_ERR(data);

		return sprintf(buf, "%d\n", !!(data->config4 & CONFIG4_MAXDUTY));
		}

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