ACPI: video - properly handle errors when registering proc elements

Have acpi_video_device_add_fs() and acpi_video_bus_add_fs()
properly unwind proc creation after error.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 3f0e4bccf9dbc43970d86ca4fce9fa4686c8fadc..87ae791781ab4e24fd8c4214a159006a0a8af9c1 100644 (file)
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -1048,87 +1048,90 @@ acpi_video_device_EDID_open_fs(struct inode *inode, struct file *file)
 
 static int acpi_video_device_add_fs(struct acpi_device *device)
 {
-       struct proc_dir_entry *entry = NULL;
+       struct proc_dir_entry *entry, *device_dir;
        struct acpi_video_device *vid_dev;
 
-
-       if (!device)
-               return -ENODEV;
-
        vid_dev = acpi_driver_data(device);
        if (!vid_dev)
                return -ENODEV;
 
-       if (!acpi_device_dir(device)) {
-               acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
-                                                    vid_dev->video->dir);
-               if (!acpi_device_dir(device))
-                       return -ENODEV;
-               acpi_device_dir(device)->owner = THIS_MODULE;
-       }
+       device_dir = proc_mkdir(acpi_device_bid(device),
+                               vid_dev->video->dir);
+       if (!device_dir)
+               return -ENOMEM;
+
+       device_dir->owner = THIS_MODULE;
 
        /* 'info' [R] */
-       entry = create_proc_entry("info", S_IRUGO, acpi_device_dir(device));
+       entry = create_proc_entry("info", S_IRUGO, device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               entry->proc_fops = &acpi_video_device_info_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_dir;
+
+       entry->proc_fops = &acpi_video_device_info_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
 
        /* 'state' [R/W] */
-       entry =
-           create_proc_entry("state", S_IFREG | S_IRUGO | S_IWUSR,
-                             acpi_device_dir(device));
+       entry = create_proc_entry("state", S_IFREG | S_IRUGO | S_IWUSR,
+                                 device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               acpi_video_device_state_fops.write = acpi_video_device_write_state;
-               entry->proc_fops = &acpi_video_device_state_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_info;
+
+       acpi_video_device_state_fops.write = acpi_video_device_write_state;
+       entry->proc_fops = &acpi_video_device_state_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
 
        /* 'brightness' [R/W] */
-       entry =
-           create_proc_entry("brightness", S_IFREG | S_IRUGO | S_IWUSR,
-                             acpi_device_dir(device));
+       entry = create_proc_entry("brightness", S_IFREG | S_IRUGO | S_IWUSR,
+                                 device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               acpi_video_device_brightness_fops.write = acpi_video_device_write_brightness;
-               entry->proc_fops = &acpi_video_device_brightness_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_state;
+
+       acpi_video_device_brightness_fops.write =
+                       acpi_video_device_write_brightness;
+       entry->proc_fops = &acpi_video_device_brightness_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
 
        /* 'EDID' [R] */
-       entry = create_proc_entry("EDID", S_IRUGO, acpi_device_dir(device));
+       entry = create_proc_entry("EDID", S_IRUGO, device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               entry->proc_fops = &acpi_video_device_EDID_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_brightness;
 
+       entry->proc_fops = &acpi_video_device_EDID_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
+
+       acpi_device_dir(device) = device_dir;
        return 0;
+
+ err_remove_brightness:
+       remove_proc_entry("brightness", device_dir);
+ err_remove_state:
+       remove_proc_entry("state", device_dir);
+ err_remove_info:
+       remove_proc_entry("info", device_dir);
+ err_remove_dir:
+       remove_proc_entry(acpi_device_bid(device), vid_dev->video->dir);
+       return -ENOMEM;
 }
 
 static int acpi_video_device_remove_fs(struct acpi_device *device)
 {
        struct acpi_video_device *vid_dev;
+       struct proc_dir_entry *device_dir;
 
        vid_dev = acpi_driver_data(device);
        if (!vid_dev || !vid_dev->video || !vid_dev->video->dir)
                return -ENODEV;
 
-       if (acpi_device_dir(device)) {
-               remove_proc_entry("info", acpi_device_dir(device));
-               remove_proc_entry("state", acpi_device_dir(device));
-               remove_proc_entry("brightness", acpi_device_dir(device));
-               remove_proc_entry("EDID", acpi_device_dir(device));
+       device_dir = acpi_device_dir(device);
+       if (device_dir) {
+               remove_proc_entry("info", device_dir);
+               remove_proc_entry("state", device_dir);
+               remove_proc_entry("brightness", device_dir);
+               remove_proc_entry("EDID", device_dir);
                remove_proc_entry(acpi_device_bid(device), vid_dev->video->dir);
                acpi_device_dir(device) = NULL;
        }
@@ -1335,94 +1338,91 @@ acpi_video_bus_write_DOS(struct file *file,
 
 static int acpi_video_bus_add_fs(struct acpi_device *device)
 {
-       struct proc_dir_entry *entry = NULL;
-       struct acpi_video_bus *video;
-
+       struct acpi_video_bus *video = acpi_driver_data(device);
+       struct proc_dir_entry *device_dir;
+       struct proc_dir_entry *entry;
 
-       video = acpi_driver_data(device);
+       device_dir = proc_mkdir(acpi_device_bid(device), acpi_video_dir);
+       if (!device_dir)
+               return -ENOMEM;
 
-       if (!acpi_device_dir(device)) {
-               acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
-                                                    acpi_video_dir);
-               if (!acpi_device_dir(device))
-                       return -ENODEV;
-               video->dir = acpi_device_dir(device);
-               acpi_device_dir(device)->owner = THIS_MODULE;
-       }
+       device_dir->owner = THIS_MODULE;
 
        /* 'info' [R] */
-       entry = create_proc_entry("info", S_IRUGO, acpi_device_dir(device));
+       entry = create_proc_entry("info", S_IRUGO, device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               entry->proc_fops = &acpi_video_bus_info_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_dir;
+
+       entry->proc_fops = &acpi_video_bus_info_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
 
        /* 'ROM' [R] */
-       entry = create_proc_entry("ROM", S_IRUGO, acpi_device_dir(device));
+       entry = create_proc_entry("ROM", S_IRUGO, device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               entry->proc_fops = &acpi_video_bus_ROM_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_info;
+
+       entry->proc_fops = &acpi_video_bus_ROM_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
 
        /* 'POST_info' [R] */
-       entry =
-           create_proc_entry("POST_info", S_IRUGO, acpi_device_dir(device));
+       entry = create_proc_entry("POST_info", S_IRUGO, device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               entry->proc_fops = &acpi_video_bus_POST_info_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_rom;
+
+       entry->proc_fops = &acpi_video_bus_POST_info_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
 
        /* 'POST' [R/W] */
-       entry =
-           create_proc_entry("POST", S_IFREG | S_IRUGO | S_IRUSR,
-                             acpi_device_dir(device));
+       entry = create_proc_entry("POST", S_IFREG | S_IRUGO | S_IRUSR,
+                                 device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               acpi_video_bus_POST_fops.write = acpi_video_bus_write_POST;
-               entry->proc_fops = &acpi_video_bus_POST_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_post_info;
+
+       acpi_video_bus_POST_fops.write = acpi_video_bus_write_POST;
+       entry->proc_fops = &acpi_video_bus_POST_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
 
        /* 'DOS' [R/W] */
-       entry =
-           create_proc_entry("DOS", S_IFREG | S_IRUGO | S_IRUSR,
-                             acpi_device_dir(device));
+       entry = create_proc_entry("DOS", S_IFREG | S_IRUGO | S_IRUSR,
+                             device_dir);
        if (!entry)
-               return -ENODEV;
-       else {
-               acpi_video_bus_DOS_fops.write = acpi_video_bus_write_DOS;
-               entry->proc_fops = &acpi_video_bus_DOS_fops;
-               entry->data = acpi_driver_data(device);
-               entry->owner = THIS_MODULE;
-       }
+               goto err_remove_post;
+
+       acpi_video_bus_DOS_fops.write = acpi_video_bus_write_DOS;
+       entry->proc_fops = &acpi_video_bus_DOS_fops;
+       entry->data = acpi_driver_data(device);
+       entry->owner = THIS_MODULE;
 
+       video->dir = acpi_device_dir(device) = device_dir;
        return 0;
+
+ err_remove_post:
+       remove_proc_entry("POST", device_dir);
+ err_remove_post_info:
+       remove_proc_entry("POST_info", device_dir);
+ err_remove_rom:
+       remove_proc_entry("ROM", device_dir);
+ err_remove_info:
+       remove_proc_entry("info", device_dir);
+ err_remove_dir:
+       remove_proc_entry(acpi_device_bid(device), acpi_video_dir);
+       return -ENOMEM;
 }
 
 static int acpi_video_bus_remove_fs(struct acpi_device *device)
 {
-       struct acpi_video_bus *video;
-
-
-       video = acpi_driver_data(device);
+       struct proc_dir_entry *device_dir = acpi_device_dir(device);
 
-       if (acpi_device_dir(device)) {
-               remove_proc_entry("info", acpi_device_dir(device));
-               remove_proc_entry("ROM", acpi_device_dir(device));
-               remove_proc_entry("POST_info", acpi_device_dir(device));
-               remove_proc_entry("POST", acpi_device_dir(device));
-               remove_proc_entry("DOS", acpi_device_dir(device));
+       if (device_dir) {
+               remove_proc_entry("info", device_dir);
+               remove_proc_entry("ROM", device_dir);
+               remove_proc_entry("POST_info", device_dir);
+               remove_proc_entry("POST", device_dir);
+               remove_proc_entry("DOS", device_dir);
                remove_proc_entry(acpi_device_bid(device), acpi_video_dir);
                acpi_device_dir(device) = NULL;
        }