staging: dgap: implement proper error handling in dgap_start()

dgap_start() ignored errors in class_create() and device_create().
The patch implements proper error handling.

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

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/dgap/dgap.c b/drivers/staging/dgap/dgap.c
index ad5afbc1e69447e7d22443416f6d68fd73dc78bb..bfafe7e3763a9356eca37ee6e0f119df28777218 100644 (file)
--- a/drivers/staging/dgap/dgap.c
+++ b/drivers/staging/dgap/dgap.c
@@ -547,6 +547,7 @@ static int dgap_start(void)
 {
        int rc = 0;
        unsigned long flags;
+       struct device *device;
 
        /*
         * make sure that the globals are
@@ -570,9 +571,18 @@ static int dgap_start(void)
                return rc;
 
        dgap_class = class_create(THIS_MODULE, "dgap_mgmt");
-       device_create(dgap_class, NULL,
+       if (IS_ERR(dgap_class)) {
+               rc = PTR_ERR(dgap_class);
+               goto failed_class;
+       }
+
+       device = device_create(dgap_class, NULL,
                MKDEV(DIGI_DGAP_MAJOR, 0),
                NULL, "dgap_mgmt");
+       if (IS_ERR(device)) {
+               rc = PTR_ERR(device);
+               goto failed_device;
+       }
 
        /* Start the poller */
        DGAP_LOCK(dgap_poll_lock, flags);
@@ -588,6 +598,12 @@ static int dgap_start(void)
        dgap_driver_state = DRIVER_NEED_CONFIG_LOAD;
 
        return rc;
+
+failed_device:
+       class_destroy(dgap_class);
+failed_class:
+       unregister_chrdev(DIGI_DGAP_MAJOR, "dgap");
+       return rc;
 }
 
 /*