staging: comedi: fix clean-up of comedi_class in comedi_init()

commit a9332e9ad09c2644c99058fcf6ae2f355e93ce74 upstream.

There is a clean-up bug in the core comedi module initialization
functions, `comedi_init()`.  If the `comedi_num_legacy_minors` module
parameter is non-zero (and valid), it creates that many "legacy" devices
and registers them in SysFS.  A failure causes the function to clean up
and return an error.  Unfortunately, it fails to destroy the "comedi"
class that was created earlier.  Fix it by adding a call to
`class_destroy(comedi_class)` at the appropriate place in the clean-up
sequence.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Cc: <stable@vger.kernel.org> # 3.9+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index 57457011ded39d2687fddf1816d40bed8838cb43..2aba2f75fb87ad34ab4c9fcc34573feb3668b04d 100644 (file)
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -2563,6 +2563,7 @@ static int __init comedi_init(void)
                dev = comedi_alloc_board_minor(NULL);
                if (IS_ERR(dev)) {
                        comedi_cleanup_board_minors();
+                       class_destroy(comedi_class);
                        cdev_del(&comedi_cdev);
                        unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
                                                 COMEDI_NUM_MINORS);