w83627ehf: Fix unchecked return status

w83627ehf: Fix unchecked return status

Fix: check return value from device_create_file()
Fix: call device_remove_file() on error and module unload
Fix: call hwmon_device_register() after device_create_file() to eliminate race

Signed-off-by: David Hubbard <david.c.hubbard@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 82 insertions, 40 deletions

diff --git a/drivers/hwmon/w83627ehf.c b/drivers/hwmon/w83627ehf.c
index 23824183e02f..7a58b079d735 100644
--- a/drivers/hwmon/w83627ehf.c
+++ b/drivers/hwmon/w83627ehf.c
@@ -4,6 +4,7 @@
     Copyright (C) 2005  Jean Delvare <khali@linux-fr.org>
     Copyright (C) 2006  Yuan Mu <Ymu@Winbond.com.tw>,
                         Rudolf Marek <r.marek@sh.cvut.cz>
+                        David Hubbard <david.c.hubbard@gmail.com>
 
     Shamelessly ripped from the w83627hf driver
     Copyright (C) 2003  Mark Studebaker
@@ -621,14 +622,6 @@ static struct sensor_device_attribute sda_in_max[] = {
        SENSOR_ATTR(in9_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 9),
 };
 
-static void device_create_file_in(struct device *dev, int i)
-{
-        device_create_file(dev, &sda_in_input[i].dev_attr);
-        device_create_file(dev, &sda_in_alarm[i].dev_attr);
-        device_create_file(dev, &sda_in_min[i].dev_attr);
-        device_create_file(dev, &sda_in_max[i].dev_attr);
-}
-
 #define show_fan_reg(reg) \
 static ssize_t \
 show_##reg(struct device *dev, struct device_attribute *attr, \
@@ -756,14 +749,6 @@ static struct sensor_device_attribute sda_fan_div[] = {
         SENSOR_ATTR(fan5_div, S_IRUGO, show_fan_div, NULL, 4),
 };
 
-static void device_create_file_fan(struct device *dev, int i)
-{
-        device_create_file(dev, &sda_fan_input[i].dev_attr);
-        device_create_file(dev, &sda_fan_alarm[i].dev_attr);
-        device_create_file(dev, &sda_fan_div[i].dev_attr);
-        device_create_file(dev, &sda_fan_min[i].dev_attr);
-}
-
 #define show_temp1_reg(reg) \
 static ssize_t \
 show_##reg(struct device *dev, struct device_attribute *attr, \
@@ -1036,15 +1021,6 @@ static struct sensor_device_attribute sda_tolerance[] = {
                     store_tolerance, 3),
 };
 
-static void device_create_file_pwm(struct device *dev, int i)
-{
-        device_create_file(dev, &sda_pwm[i].dev_attr);
-        device_create_file(dev, &sda_pwm_mode[i].dev_attr);
-        device_create_file(dev, &sda_pwm_enable[i].dev_attr);
-        device_create_file(dev, &sda_target_temp[i].dev_attr);
-        device_create_file(dev, &sda_tolerance[i].dev_attr);
-}
-
 /* Smart Fan registers */
 
 #define fan_functions(reg, REG) \
@@ -1131,6 +1107,39 @@ static struct sensor_device_attribute sda_sf3_arrays[] = {
  * Driver and client management
  */
 
+static void w83627ehf_device_remove_files(struct device *dev)
+{
+        /* some entries in the following arrays may not have been used in
+         * device_create_file(), but device_remove_file() will ignore them */
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(sda_sf3_arrays); i++)
+                device_remove_file(dev, &sda_sf3_arrays[i].dev_attr);
+        for (i = 0; i < ARRAY_SIZE(sda_sf3_arrays_fan4); i++)
+                device_remove_file(dev, &sda_sf3_arrays_fan4[i].dev_attr);
+        for (i = 0; i < 10; i++) {
+                device_remove_file(dev, &sda_in_input[i].dev_attr);
+                device_remove_file(dev, &sda_in_alarm[i].dev_attr);
+                device_remove_file(dev, &sda_in_min[i].dev_attr);
+                device_remove_file(dev, &sda_in_max[i].dev_attr);
+        }
+        for (i = 0; i < 5; i++) {
+                device_remove_file(dev, &sda_fan_input[i].dev_attr);
+                device_remove_file(dev, &sda_fan_alarm[i].dev_attr);
+                device_remove_file(dev, &sda_fan_div[i].dev_attr);
+                device_remove_file(dev, &sda_fan_min[i].dev_attr);
+        }
+        for (i = 0; i < 4; i++) {
+                device_remove_file(dev, &sda_pwm[i].dev_attr);
+                device_remove_file(dev, &sda_pwm_mode[i].dev_attr);
+                device_remove_file(dev, &sda_pwm_enable[i].dev_attr);
+                device_remove_file(dev, &sda_target_temp[i].dev_attr);
+                device_remove_file(dev, &sda_tolerance[i].dev_attr);
+        }
+        for (i = 0; i < ARRAY_SIZE(sda_temp); i++)
+                device_remove_file(dev, &sda_temp[i].dev_attr);
+}
+
 static struct i2c_driver w83627ehf_driver;
 
 static void w83627ehf_init_client(struct i2c_client *client)
@@ -1217,37 +1226,69 @@ static int w83627ehf_detect(struct i2c_adapter *adapter)
                 data->has_fan |= (1 << 4);
 
         /* Register sysfs hooks */
-        data->class_dev = hwmon_device_register(dev);
-        if (IS_ERR(data->class_dev)) {
-                err = PTR_ERR(data->class_dev);
-                goto exit_detach;
-        }
-
         for (i = 0; i < ARRAY_SIZE(sda_sf3_arrays); i++)
-                device_create_file(dev, &sda_sf3_arrays[i].dev_attr);
+                if ((err = device_create_file(dev,
+                        &sda_sf3_arrays[i].dev_attr)))
+                        goto exit_remove;
 
         /* if fan4 is enabled create the sf3 files for it */
         if (data->has_fan & (1 << 3))
-                for (i = 0; i < ARRAY_SIZE(sda_sf3_arrays_fan4); i++)
-                        device_create_file(dev, &sda_sf3_arrays_fan4[i].dev_attr);
+                for (i = 0; i < ARRAY_SIZE(sda_sf3_arrays_fan4); i++) {
+                        if ((err = device_create_file(dev,
+                                &sda_sf3_arrays_fan4[i].dev_attr)))
+                                goto exit_remove;
+                }
 
         for (i = 0; i < 10; i++)
-                device_create_file_in(dev, i);
+                if ((err = device_create_file(dev, &sda_in_input[i].dev_attr))
+                        || (err = device_create_file(dev,
+                                &sda_in_alarm[i].dev_attr))
+                        || (err = device_create_file(dev,
+                                &sda_in_min[i].dev_attr))
+                        || (err = device_create_file(dev,
+                                &sda_in_max[i].dev_attr)))
+                        goto exit_remove;
 
         for (i = 0; i < 5; i++) {
                 if (data->has_fan & (1 << i)) {
-                        device_create_file_fan(dev, i);
-                        if (i != 4) /* we have only 4 pwm */
-                                device_create_file_pwm(dev, i);
+                        if ((err = device_create_file(dev,
+                                        &sda_fan_input[i].dev_attr))
+                                || (err = device_create_file(dev,
+                                        &sda_fan_alarm[i].dev_attr))
+                                || (err = device_create_file(dev,
+                                        &sda_fan_div[i].dev_attr))
+                                || (err = device_create_file(dev,
+                                        &sda_fan_min[i].dev_attr)))
+                                goto exit_remove;
+                        if (i < 4 && /* w83627ehf only has 4 pwm */
+                                ((err = device_create_file(dev,
+                                        &sda_pwm[i].dev_attr))
+                                || (err = device_create_file(dev,
+                                        &sda_pwm_mode[i].dev_attr))
+                                || (err = device_create_file(dev,
+                                        &sda_pwm_enable[i].dev_attr))
+                                || (err = device_create_file(dev,
+                                        &sda_target_temp[i].dev_attr))
+                                || (err = device_create_file(dev,
+                                        &sda_tolerance[i].dev_attr))))
+                                goto exit_remove;
                 }
         }
 
         for (i = 0; i < ARRAY_SIZE(sda_temp); i++)
-                device_create_file(dev, &sda_temp[i].dev_attr);
+                if ((err = device_create_file(dev, &sda_temp[i].dev_attr)))
+                        goto exit_remove;
+
+        data->class_dev = hwmon_device_register(dev);
+        if (IS_ERR(data->class_dev)) {
+                err = PTR_ERR(data->class_dev);
+                goto exit_remove;
+        }
 
         return 0;
 
-exit_detach:
+exit_remove:
+        w83627ehf_device_remove_files(dev);
         i2c_detach_client(client);
 exit_free:
         kfree(data);
@@ -1263,6 +1304,7 @@ static int w83627ehf_detach_client(struct i2c_client *client)
         int err;
 
         hwmon_device_unregister(data->class_dev);
+        w83627ehf_device_remove_files(&client->dev);
 
         if ((err = i2c_detach_client(client)))
                 return err;