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Date: Wed, 17 Sep 2025 14:48:44 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Donet Tom <donettom@linux.ibm.com>
Cc: Chris Mason <clm@meta.com>, David Hildenbrand <david@redhat.com>, Oscar
 Salvador <osalvador@suse.de>, Zi Yan <ziy@nvidia.com>, Greg Kroah-Hartman
 <gregkh@linuxfoundation.org>, Ritesh Harjani <ritesh.list@gmail.com>,
 linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Rafael J . Wysocki"
 <rafael@kernel.org>, Danilo Krummrich <dakr@kernel.org>, Jonathan Cameron
 <Jonathan.Cameron@huawei.com>, Alison Schofield
 <alison.schofield@intel.com>, Yury Norov <yury.norov@gmail.com>, Dave Jiang
 <dave.jiang@intel.com>, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Subject: Re: [PATCH v2] drivers/base/node: Handle error properly in
 register_one_node()
Message-Id: <20250917144844.e8d9b9593aac9f3a4b52a0cb@linux-foundation.org>
In-Reply-To: <676712d1-7b4f-4614-bd82-5b0c43881865@linux.ibm.com>
References: <20250917134604.2149316-1-clm@meta.com>
	<676712d1-7b4f-4614-bd82-5b0c43881865@linux.ibm.com>
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On Wed, 17 Sep 2025 20:25:48 +0530 Donet Tom <donettom@linux.ibm.com> wrote:

> > Can this cause a double-free? Looking at register_node(), when
> > device_register() fails, it calls put_device(&node->dev). The put_device()
> > call triggers node_device_release() which does kfree(to_node(dev)), freeing
> > the entire node structure. So when register_node() returns an error, the
> > node memory is already freed, but this code calls kfree(node) again on the
> > same memory.
> >
> > The call chain is: register_node()->device_register() fails->
> > put_device()->node_device_release()->kfree(to_node(dev)).
> 
> 
> Thank you for pointing this out. I will address it and send a v3.

This patch is now in mm.git's non-rebasing mm-stable branch, so no
replacements, please.

A standalone patch with 

	Fixes: 786eb990cfb7 ("drivers/base/node: handle error properly in register_one_node()")

is the way to go.