[ 070/108] HID: hidraw: improve error handling in hidraw_init()

Ben Hutchings
2012-10-07T23:36:57Z

From: Alexey Khoroshilov <khoroshilov@ispras.ru>

commit bcb4a75bde3821cecb17a71d287abfd6ef9bd68d upstream.

Several improvements in error handling:
- do not report success if alloc_chrdev_region() failed
- check for error code of cdev_add()
- use unregister_chrdev_region() instead of unregister_chrdev()
if class_create() failed

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/hid/hidraw.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
index 3b6f7bf..7c47fc3 100644
--- a/drivers/hid/hidraw.c
+++ b/drivers/hid/hidraw.c
@@ -559,21 +559,28 @@ int __init hidraw_init(void)

if (result < 0) {
pr_warn("can't get major number\n");
- result = 0;
goto out;
}

hidraw_class = class_create(THIS_MODULE, "hidraw");
if (IS_ERR(hidraw_class)) {
result = PTR_ERR(hidraw_class);
- unregister_chrdev(hidraw_major, "hidraw");
- goto out;
+ goto error_cdev;
}

cdev_init(&hidraw_cdev, &hidraw_ops);
- cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
+ result = cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
+ if (result < 0)
+ goto error_class;
+
out:
return result;
+
+error_class:
+ class_destroy(hidraw_class);
+error_cdev:
+ unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
+ goto out;
}

void hidraw_exit(void)