Patch "mISDN: fix possible memory leak in mISDN_register_device()" has been added to the 4.9-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    mISDN: fix possible memory leak in mISDN_register_device()

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     misdn-fix-possible-memory-leak-in-misdn_register_dev.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 32bccf2f5c7f805f4c93ef75cc8431172fc37ef1
Author: Yang Yingliang <yangyingliang@xxxxxxxxxx>
Date:   Mon Oct 31 20:13:40 2022 +0800

    mISDN: fix possible memory leak in mISDN_register_device()
    
    [ Upstream commit e7d1d4d9ac0dfa40be4c2c8abd0731659869b297 ]
    
    Afer commit 1fa5ae857bb1 ("driver core: get rid of struct device's
    bus_id string array"), the name of device is allocated dynamically,
    add put_device() to give up the reference, so that the name can be
    freed in kobject_cleanup() when the refcount is 0.
    
    Set device class before put_device() to avoid null release() function
    WARN message in device_release().
    
    Fixes: 1fa5ae857bb1 ("driver core: get rid of struct device's bus_id string array")
    Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
    Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/isdn/mISDN/core.c b/drivers/isdn/mISDN/core.c
index f5a06a6fb297..5cd53b2c47c7 100644
--- a/drivers/isdn/mISDN/core.c
+++ b/drivers/isdn/mISDN/core.c
@@ -242,11 +242,12 @@ mISDN_register_device(struct mISDNdevice *dev,
 	if (debug & DEBUG_CORE)
 		printk(KERN_DEBUG "mISDN_register %s %d\n",
 		       dev_name(&dev->dev), dev->id);
+	dev->dev.class = &mISDN_class;
+
 	err = create_stack(dev);
 	if (err)
 		goto error1;
 
-	dev->dev.class = &mISDN_class;
 	dev->dev.platform_data = dev;
 	dev->dev.parent = parent;
 	dev_set_drvdata(&dev->dev, dev);
@@ -258,8 +259,8 @@ mISDN_register_device(struct mISDNdevice *dev,
 
 error3:
 	delete_stack(dev);
-	return err;
 error1:
+	put_device(&dev->dev);
 	return err;
 
 }