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Date: Mon, 6 Oct 2025 11:03:17 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Zhu Yanjun <yanjun.zhu@linux.dev>
Cc: Pavel Zhigulin <Pavel.Zhigulin@kaspersky.com>, Ayush Sawal
 <ayush.sawal@chelsio.com>, Andrew Lunn <andrew+netdev@lunn.ch>, "David S.
 Miller" <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>, Paolo
 Abeni <pabeni@redhat.com>, Leon Romanovsky <leon@kernel.org>, Steffen
 Klassert <steffen.klassert@secunet.com>, Cosmin Ratiu <cratiu@nvidia.com>,
 Harsh Jain <harsh@chelsio.com>, Atul Gupta <atul.gupta@chelsio.com>,
 Herbert Xu <herbert@gondor.apana.org.au>, Ganesh Goudar
 <ganeshgr@chelsio.com>, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org
Subject: Re: [PATCH] net: fix potential use-after-free in
 ch_ipsec_xfrm_add_state() callback
Message-ID: <20251006110317.39d08275@kernel.org>
In-Reply-To: <f0cef998-0d49-4a52-b1b8-2f89b81d4b07@linux.dev>
References: <20251001111646.806130-1-Pavel.Zhigulin@kaspersky.com>
	<f0cef998-0d49-4a52-b1b8-2f89b81d4b07@linux.dev>
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On Fri, 3 Oct 2025 21:28:51 -0700 Zhu Yanjun wrote:
> When the function ch_ipsec_xfrm_add_state is called, the kernel module 
> cannot be in the GOING or UNFORMED state.

That was my intuition as well, but on a quick look module state is set
to GOING before ->exit() is called. So this function can in fact fail
to acquire a reference.

Could you share your exact analysis?