[media] lirc: fix error paths in lirc_cdev_add()

"c77d17c0 [media] lirc: use-after free" introduces two problems:
cdev_del() can be called with a NULL argument, and the kobject_put()
path will cause a double free.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 3 insertions, 5 deletions

diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c
index d3039efb4e7c..3854809e8531 100644
--- a/drivers/media/rc/lirc_dev.c
+++ b/drivers/media/rc/lirc_dev.c
@@ -157,13 +157,13 @@ static const struct file_operations lirc_dev_fops = {
 
 static int lirc_cdev_add(struct irctl *ir)
 {
-        int retval = -ENOMEM;
         struct lirc_driver *d = &ir->d;
         struct cdev *cdev;
+        int retval;
 
         cdev = cdev_alloc();
         if (!cdev)
-                goto err_out;
+                return -ENOMEM;
 
         if (d->fops) {
                 cdev->ops = d->fops;
@@ -177,10 +177,8 @@ static int lirc_cdev_add(struct irctl *ir)
                 goto err_out;
 
         retval = cdev_add(cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
-        if (retval) {
-                kobject_put(&cdev->kobj);
+        if (retval)
                 goto err_out;
-        }
 
         ir->cdev = cdev;